Originally aired Dateline NBC on Aug. 13.
Teri Lee: He followed me home … You know, it's creepy to have someone following you home.
Her name is Teri Lee. She's a single mother of four, afraid and maybe a little embarrassed.
Teri Lee: It's terribly humiliating
She's sitting in a Minnesota police station, doing something she never thought she'd have to do: being interrogated by a detective.
Teri Lee: This is disturbing to me because it's the third incident.
It's the third time Teri has had to talk with the cops about her ex-boyfriend. She says he's a man who just will not leave her alone, a man who's exposed her to a world of seedy sex. It's a world she doesn't want any part of.
Teri Lee: I didn't know that, that this was so out there.
But this day was just the beginning of Teri Lee's education in the darker ways of the world. Over the next four months, the 38-year-old would swap her routine life of PTA meetings and family get-togethers for a life of terror.
It would be a life that would test Teri and test her family and a life that would raise basic questions about who you can trust…
Hoda Kotb: It seemed like his whole life was a lie, didn't it?
Rachelle Ebner: Yes.
...and questions about who you can count on to protect you
Carolyn: Someone should have listened and helped.
It was all so far from Teri's beginnings.
Born into a loving family in a cozy St. Paul suburb, she was a high-spirited child nicknamed "T-Bop."
As a child, Teri would spend lazy summer afternoons at her parents' cabin on Big Marine Lake, splashing around in the water. Several years later you could still find her there on most weekends, splashing around with her children.
Vicki Swenson: It was my great grandparents [who] built it so it's been in the family for years. It really was a place for gathering, for food, just to build relationships. It's a good time.
It was at the lake house that Teri taught her younger sister, Vicki, to read. Just one of many life lessons Teri would teach her
Vicki Swenson [Teri's sister]: She was always that first person to call, the first person to find down the hallway when we were in school. You know that something was wrong, and she always said "Everything is OK."
"Everything is OK." It was Teri's catchphrase, said with a grin as she barrelled through high school. She was a gutsy athlete and a trusted girlfriend. And who could forget prom night?
Carolyn: We all gathered at Teri's house, kind of did the walk-through parade through her house. It was a special time
Here Teri is 17 years old, brimming with excitement as she joins the class of '86's Homecoming Parade. Teri was just as excited about her future.
The announcer at her Homecoming Parade said "She plans on going to college and someday settling down and getting married."
That dream came true in 1994 when she married Ty Lee, her junior high crush.
Carolyn: It was a really good fit. I could see it when they got married.
That same year, Teri gave birth to her first child, Taylor.
And then came Tyler, Trevor and Tara. Four children with T-names, just like their mom and dad. You could see them all speeding across the water at the lake house, sun-kissed and laughing.
Vicki Swenson: They worked really hard to buy a boat. There went Ty. That was his job for the day, was pulling kids on the tube. They very much valued being a family.
But Teri's family was about to be torn apart.
It happened on a dark county road, one winter night in 2001. Ty was driving home after a long day's work when he fell asLeep at the wheel. His truck swerved across the highway and hit a ditch.
Melissa Enge: It just soared into the trees, jumped over the driveway, hit one of those trees and then just tumbled.
Melissa Enge and her boyfriend, who had stopped to help, found Ty pinned under the cab of his truck. He had one thing on his mind.
Bill Enge: He was asking about his little girl … how she was.
Teri and Ty's eldest daughter, Taylor, had been asLeep in the passenger seat at the time of the accident. Now she sat by the side of the road
Melissa Enge: She was just upset. Crying.
A few hours later, Teri called her close friend Carolyn with terrible news. Taylor was OK but her husband Ty was dead.
Carolyn: Went down to the hospital right away and she was sitting there with a bag of his watch and his wallet and his things, and she was devastated. Just devastated.
Friends offered to pay bills and to help with child-care but Teri refused. She would say "Everything is OK."
Vicki Swenson: I think she knew everything wasn't OK but she didn't want anyone else to know. That woman was tough. Just incredibly resilient and strong.
Teri threw herself into her part-time job at 3M, the manufacturing company headquartered in Minnesota. Working there seemed a safe bet to Teri. That's where her friend Carolyn worked.
Little did Teri know that she was about to begin a dangerous journey.
Surrounded by friends and family after the death of her husband, Teri Lee hardly had a minute to herself. But she was often lonely.
Vicki Swenson: It's scary, I think, when you're 33 years old and widowed with four children. How do you meet someone? It's common to have that desire for human companionship.
Teri found that companionship at work. Nearly a year after the accident, a 42-year-old technician in 3M's labs started stopping by her desk each day to chat.
Carolyn: And she thought that was really nice. And then they started seeing more of each other.
The man's name was Steve Van Keuren. Like Teri, he was a local kid made good. He had grown up across the St. Croix River in Wisconsin.
Deb Van Keuren: He was always playing softball. If you couldn't find him at home that's where he was
Van Keuren's sister, Deb, says her brother was a sports nut – just like Teri. Once a high school football jock, he now spent his free time playing softball with other 3M employees. Teri was on the team.
Deb Van Keuren: That's how it started. Him and Teri were playing softball together and then volleyball.
Van Keuren seemed like a godsend to the widowed mother of four.
Carolyn: He would pick up kids for her. You know pick up and drop off from school, bring them to activities. He would help make dinner
And Van Keuren relished playing dad to Teri's kids. He didn't have any children of his own.
Deb Van Keuren: Steve enjoyed having the kids around. The kids were good for Steve.
Van Keuren even lent Teri money to move the kids into a house in an affluent subdivision. Perry and Rachelle Ebner became fast friends with their new neighbor.
Rachelle Ebner: I thought it's great because we really had, at that time, had no kids around to play with our kids.
Perry Ebner: She's very wholesome, very friendly. She fit perfect in the community.
Van Keuren seemed a little more reserved to them. Perhaps he was a bit shy.
Rachelle Ebner: He seemed nice. You know, kind of just answered questions, though, and didn't disclose too much.
Teri's sister was less accepting of Van Keuren. Something about him bothered her. Christmas in 2005 was a far cry from Teri and Ty's boisterous holiday parties.
Van Keuren didn't seem interested in getting to know the family
Vicki: I remember feeling sorry for my sister. We're all having a great time. He's sitting in the other room. She sat half way between the two
As time passed, Vicki says she was seeing her sister less and less. She rarely showed up at the lake house.
Vicki Swenson: Just even her phone calls to me weren't as frequent.
Teri's childhood friend Carolyn noticed the same thing
Carolyn: I didn't spend a lot of time with him and her together.
Hoda Kotb [Dateline correspondent]: Was that odd that you didn't?
Teri confided in Carolyn that Van Keuren had become very controlling.
Hoda Kotb: What did she say about that?
Carolyn: Just that it bothered her and you know, "I can never do anything right."
Teri tried to end it with Van Keuren a couple of times but she always came back to him.
Carolyn: She didn't want to break up that relationship with her kids. They knew him as a kind of father figure.
But Van Keuren was becoming a rather domineering father figure, according to Teri's eldest daughter, Taylor.
Taylor Lee: He put down a lot of new rules, I think, like we couldn't go barefoot in the house and stuff.
Hoda Kotb: What happens if you did go barefoot in the house?
Taylor Lee: We had to pay him a quarter. I think he just liked being the boss of everything and that made him feel good.
They'd been dating nearly three years when Teri discovered there was something else that made Van Keuren feel good.
Rachelle Ebner [neighbor and friend]: She kept finding all these slips of paper, little notes, you know, 38 double-D, 52. And she said, "Now what does that mean to you?" and I thought, "Well, bra size and age?" and she said, "Exactly."
Van Keuren finally admitted to Teri that he'd been seeing prostitutes
Hoda Kotb: How long had this been going on?
Rachelle Ebner: From what she had figured through what he had told her, it was during the whole course of their relationship.
Teri tried to end it with Van Keuren for good. But he didn't seem able to let go.
Carolyn: He would call her and leave a message on her phone and say "I know you don't want to see me anymore but call me every half an hour today. Tell me where you are and just say hi."
Hoda Kotb: Every half an hour?
Video: Phone numbers in his pockets And the barrage of calls didn't stop. In May 2006, Van Keuren called Teri at work and told her he had a job interview at a local strip club. Disgusted, she told him to leave her alone but there he was that night in her son's school gym.
Teri Lee: I happened to notice him off in the corner. He'd already made contact with my kids.
Teri Lee: He was standing there talking to one of them
Detective: Sure. Ok
This is Teri explaining to a detective at the Washington County sheriff's office what happened next.
Teri Lee: And when we were leaving I asked him where he was parked. Well sure enough, he's parked right behind me.
Teri and Van Keuren started to argue by their cars.
Teri Lee: I opened my door as quickly as I could and shut it as quickly as I could
Teri told the detective that Van Keuren had put his hand out to stop her getting in. Teri had slammed the door on his hand.
Detective: It sounds like you didn't know…
Teri Lee: I had no idea...
Detective: …his hand was caught there. He's saying that you intentionally did it and it turns out that's not the case.
Teri Lee: No.
Teri Lee: No.
It turns out, Teri was sitting in the interrogation room at the Washington County sheriff's office because Van Keuren had accused her of assault.
Teri said the idea of her being a threat to her ex was laughable. For starters, he was twice her size.
Teri Lee: He's much bigger than me. And he's three times stronger than me.
The detective decided not to charge Teri. He closed the case and told her not to worry
Detective: Don't sweat this, I mean…
Teri Lee: Well, I do.
Teri was growing more than a little alarmed by Van Keuren's bizarre behavior.
Hoda Kotb: Was it clear that she was afraid of him, Taylor?
Taylor Lee: Yes.
Living with fear was about to become a way of life for Teri and her family
Teri Lee had made a disturbing discovery about her boyfriend. He was hooked on meeting prostitutes in hotel rooms.
Rachelle Ebner: After she had found out all this information, it's like, "There's no way that I could live with somebody like this."
But months after they had broken up, Van Keuren wouldn't leave Teri alone. There were the constant calls and surprise visits.
Rachelle Edner: One time I was on the phone with her and I just happened to be looking out my front door as I'm talking to her. And I'm like, "Oh, he's pulling up in your driveway."
Hoda Kotb: What did she say?
Rachelle Ebner: She just sat there quietly on the phone until he left.
Van Keuren wasn't just keeping tabs on Teri. If her boys were playing in a baseball game, he would be there on the sidelines, watching from his car.
Vicki Swenson: We took it as "Oh, he must miss the kids. Wants to see them play baseball." But now I think no, that was his way of making her feel threatened.
But in the summer of 2006, Teri had someone new in her life -- someone who had promised to protect her.
Carolyn: I could see that look in her eye again that I hadn't seen for a really long time.
Hoda Kotb: What was the look?
Carolyn: She just has this sparkle in her eye when -- and she kind of cocks her head to the side. And if you knew her, you know it. And I hadn't seen that for years.
The man behind that look was 47-year-old Tim Hawkinson. Another 3M employee, he was the divorced father of three boys who adored him.
Tim Hawkinson, Jr.: He was a fun person. I mean, as kids you'd you know "How much do you love me?" And you'd put your arms up and he'd grab you and tickle you. It was just one of those fun little things.
But as happy as they were, the new couple could feel Van Keuren's shadow hanging over them. They were afraid to be seen in public together, afraid of what he might do.
Tim Hawkinson, Jr.: My dad purposefully stayed out of the picture, just for the reason of not wanting to escalate the situation.
But Van Keuren was about to escalate the situation all by himself.
Early morning, on July 29th 2006. Teri was driving home when she thought she saw Van Keuren staking out her house. By the time she pulled into the driveway, his car was gone but beer cans littered the yard. There was even one perched on her mailbox. She panicked when she saw the back door to her house was ajar. Teri rushed to her neighbor's house to call police.
Teri Lee: Looks like someone's been in my house while I've been gone.
Police officers were searching Teri's home when the phone rang. It was Van Keuren.
Rachelle Ebner: The police had her tell him at that time that he was no longer welcome at the residence.
The officers gave Van Keuren a verbal warning: if he came back to the house it would be considered trespassing.
Teri was still scared. According to this incident report, she told the officers that she was extremely fearful of Van Keuren and "that he might do something really crazy." The officers told Teri not to worry and that she could call them "for further assistance at any time". Then they left.
Twenty minutes later, Teri called Rachelle to give her an update. Their conversation was interrupted as Van Keuren came rushing through Teri's front door.
Rachelle Ebner: I just heard her scream repeatedly. And it was horrifying. I mean, it was just a horrific scream and then I heard his voice and I ran to the door to look out the window.
Hoda Kotb: What did you think was going on in there?
Rachelle Ebner: I had no idea. I knew he was very mad. I was afraid he was going to hurt her.
And then the phone went dead. Rachelle called 911.
Rachelle Ebner: I need somebody to respond to my neighbor's house.
Rachelle peered out the window, desperate to know what was going on. Two minutes later, she saw Van Keuren leaving. Then relief: Teri came stumbling outside.
Rachelle Ebner: She was running and just panting and shaking uncontrollably. She collapsed at my feet on the lawn. And she said, "He had two big knives."
Vicki Swenson: She called my parents and said "Get out of the house."
Terror suddenly seized Teri. Her parents were watching the kids. Maybe Van Keuren would come after them.
But two Washington County squad cars were closing in on Van Keuren. They had spotted him on Interstate 94 making his way from Minnesota into Wisconsin.
They arrested Van Keuren at his father's farmhouse still clutching the knives.
Van Keuren's sister could not believe what he had done.
Deb Van Keuren: Dad called me and I had, he had to repeat it a couple of times. It just … it just wasn't him.
Teri's sister raced to meet her at the one safe place they knew, the place that had been associated with good times but was now their family's shelter. The lake house.
Vicki Swenson: Her face was bruised. Her body was bruised. Her arms, her back and … I grabbed her face with my hands and said "I love you, I need you. I need you to be OK."
But perhaps for the first time in the two sisters' lives, Teri did not think everything was OK. Teri told her sister how Van Keuren had charged through the door and lunged at her with two butcher knives.
Vicki Swenson: She positioned herself so that she had the dining room table between the two of them. He would chase her, would put one knife down, try to get her with one arm and then try to stab her with the other knife.
Vicki felt sick when Teri told her what Van Keuren had been yelling.
Vicki Swenson: He said to her "This is the only way we'll be together forever." For him to kill her and then kill himself.
Teri Lee had thought she was going to die when her ex-boyfriend stormed through her front door brandishing two knives.
Tim Hawkinson, Jr.: She was freaked out. She had this look of, you know, it's obviously shock and fear.
Now her attacker sat in the same police station Teri had sat in all those months ago, being interviewed by the same detective.
Detective: Why did you bring those knives there?
Van Keuren: Mostly to maybe straighten her out.
Detective: Um. Did you try to stab at her?
Van Keuren: No, I did not...
Detective: Um. Did you tell her you were going to kill her?
Van Keuren: I might have.
Teri told her sister the detective didn't seem to take the incident seriously.
Vicki Swenson: She was outraged because he told her, "You've got nothing to worry about. I've talked to him. It'll be OK" and she called me just furious. How does he know?
Vicki says her sister also told her the prosecutors at the Washington County attorney's office didn't seem to have time for her case.
Vicki Swenson: They wanted her to drop the charges do you think?
Hoda Kotb: Why would they want her to drop the charges?
Vicki Swenson: I just don't think she was taken seriously.
Nonetheless, on Aug. 1, 2006, prosecutors did charge Van Keuren with two counts of first-degree burglary, one count of making terroristic threats, and one count of second-degree assault.
Teri was there for his arraignment, even though she was terrified to be in the same room as him.
Vicki Swenson: She was very clear, "He wants me dead. You should see the way he stares at me in court. Stares daggers at me." But that was his way again of "I'm here. I'm intmidating you. I'm trying to make you afraid."
Teri was given the chance to speak in court. She implored the judge to set Van Keuren's bail so high he couldn't afford it. She said she felt "physically threatened" by him and was sure "he will come back to my home." Video: Ex-boyfriend doesn’t remember stabbing at Teri Lee
But Teri was disappointed when the judge set bail at $75,000. Van Keuren's family paid the 10% deposit and $7,500 later he was released pending trial.
Vicki Swenson: Her words on phone later that day were, "There is no doubt in my mind he will kill me." [Crying] She knew.
The judge imposed a "no contact" order on Van Keuren. Like a restraining order, this piece of paper banned him from having any direct or indirect contact with Teri and her children. If he violated that order, he would be sent back to jail.
That afternoon the sheriff's office left Teri a voicemail giving her the number of a domestic violence hotline. The prosecutors office gave Teri information about a woman's shelter. Then, two days after Van Keuren's release, the detective handling her case told officers to send extra patrols past Teri's house. But Teri didn't think any of this would deter Van Keuren. She decided to take steps to protect herself.
Her boyfriend, Tim Hawkinson, paid for a state-of-the-art alarm system to be installed at Teri's house. He drilled Teri's four children on how to use it.
Vicki Swenson: They knew exactly how it worked. They knew the security code. They knew where the panic button was.
Hoda Kotb: What a horrible way to live.
Vicki Swenson: They were very well trained.
Hawkinson, an expert hunter, took other precautions too. He wore a handgun on his body at all times and practiced his marksmanship at a local gun range.
Tim Hawkinson, Jr.: I think he knew this guy would break in. I really think he knew that and I think he thought he would end up having to shoot this guy.
As she waited for Van Keuren to stand trial, Teri began a strange new life. It was the life of a fugitive.
Some nights she was so spooked she stayed over at Tim Hawkinson's house and if he left town on business she often went with him, taking her kids along too. Ironically these were some of their last good times as a family.
Vicki Swenson: The kids, they loved it. There were water parks. It was fun. Teri would call and Tim was in the background yelling, "Tell Vicki. We're on the run." And they were.
Teri was now working out of an undisclosed location at 3M. So it was pure chance that she bumped into her childhood friend Carolyn one day in the corridor. Carolyn could see all the stress was taking its toll on Teri.
Carolyn: She said "I'm losing my hair … I went to see my doctor, he said it's stress related."
Hoda Kotb: Her hair was falling out in clumps?
Teri told her friend she just didn't feel safe.
She kept getting these strange hang-up calls. She had a feeling she was being watched but because she couldn't prove anything, the cops had told her there was nothing they could do.
Carolyn: All of the decisions that she made in her everyday life were dependent on, OK, could he be there? Could he get at me? Am I vulnerable in this spot for him to come back and try and kill me?
But most of all Teri was worried for her kids.
Taylor Lee: She was very protective. She told us to -- if he tried to pick us up at school just to turn around, say no, and go to the principal's office.
On Sept. 20, 2006, Teri's worst fears seemed to be coming true.
It's 4:07 p.m.. Surveillance video captures Van Keuren striding into Taylor's volleyball game. He is standing by the doorway when she notices him
Taylor Lee: He just looked like a cold statue to me, like he didn't move. He just-- he tried to hide behind a pole.
Hoda Kotb: what was the first thing you thought?
Taylor Lee: I was afraid that he was going to come and get me and take me away.
Taylor's volleyball coach Judy White remembers how frightened Taylor was.
Judy White: She kept saying "That man is here. That man who tried to kill my mother. He's here. He's here. He's going to kill me."
She took Taylor to the principal's office.
Taylor Lee: He called my mom and he was all calm and my mom would-- just was freaking out. She's just like, "Well, call 911. Why did you call me?"
It took 20 minutes for the principal to corroborate Taylor's story and call 911. That 20-minute delay was all Van Keuren needed to slip away. He was gone when the cops arrived, and nobody knew where he was headed.
Teri Lee was desperate. The man who had attacked her with a knife -- the man she feared would kill her -- had crashed her daughter's volleyball game.
Taylor Lee: I was afraid that he was going to come and get me and take me away.
A court had ordered Van Keuren to stay away from Teri and her family. Van Keuren had ignored that order when he showed up at the volleyball game. Even so, local police never crossed state lines to arrest him at his home in Wisconsin. Teri called her neighbors in frustration.
Teri Lee: They won't go to his house to get him. They'd actually ... Because he lives in Wisconsin, he'll actually have to come back here to get picked up.
She couldn't believe that the bridge separating Minnesota from Wisconsin sheltered Van Keuren from arrest but left her vulnerable to his next attack.
The day after the volleyball incident Teri told her sister she was going to demand answers from the people who were supposed to be protecting her.
Vicki Swenson: I need to call the prosecutor, the D.A., the deputy sheriff that I've been working with.
But the deputy sheriff was out sick and according to Teri's sister, no one else returned her calls. So once again Teri did what she could -- on her own -- to try and protect her family. She scrambled to find photos of Van Keuren so she could give them out to her kids' teachers. If he showed up at one of their schools again, she wanted them to call 911 as quickly as possible so police could respond before he got away.
Vicki Swenson: She had all these pictures developed, $140 worth of pictures, just frantically looking for one of him maybe in the background or something.
Across that bridge in Wisconsin, Van Keuren was making preparations of his own. He rented a car, one Teri wouldn't recognize, and drove to his dad's house. Then he stole a .22 caliber handgun from his dad's gun cabinet . Now he was armed.
It's the evening of Sept. 21. Teri's neighbors, the Ebners, get ready for bed. Rachelle's husband Perry does something he doesn't normally do.
Perry Ebner: That's one of the first times I put my pistol up in my bedroom.
Hoda Kotb: Why did you do that?
Perry Ebner: Just had a feeling. I don't know.
Teri and her family prepare to go to bed as well. The four kids say a prayer Teri's boyfriend has taught them
Taylor Lee: "Dear father in heaven, look down from above…"
Teri's daughter Taylor is still too scared to sleep alone. She piles into bed with her mom and Tim, who is sleeping over.
Early morning, Sept. 22, 2006. Van Keuren drives to his dad's house and drops a chilling note in his mailbox. It says "Dad, my only dad ... I'm sorry. I had to do it ... greatest dad in the world ... I had it with her."
At 3:29 a.m., Steve Van Keuren leaves a voicemail for a former work colleague at 3M.
Van Keuren: I'm going to take Teri's life and my life because she doesn't deserve to live.
Thirty minutes later, Van Keuren is outside Teri's house. He methodically cuts the phone lines and uses a crowbar to smash his way through the patio door.
Vicki Swenson: The boys woke up to the sound of the breaking glass. Taylor woke up to gunshots.
Taylor sees Van Keuren standing at the foot of the bed and buries her head in the pillows.
Taylor Lee: I was so scared. I felt like the covers were the only thing that could protect me. I could hear the gunshots just going everywhere like at nothing, just everywhere, and then I heard my mom screaming, "No, please don't. Don't."
Taylor flees the bedroom and grabs her six-year-old sister who is standing dazed in the corridor.
Taylor Lee: We hid in the bathroom. We locked the door and we waited there. And then we didn't hear anything. And so I was scared that he was standing outside the door. I tried to tell him like, "Oh, we think you're so great."
But Van Keuren doesn't respond. The girls wait 10 minutes before creeping to their brothers' room. It is empty. They can now hear Van Keuren on the phone in Teri's bedroom. He tells someone "I shot Teri. I shot her dead." Taylor and Tara decide to make a run for it.
Taylor Lee: I just told her, and I think she knew it, too, that we had to get out of there.
As they make their escape, heading to their neighbors' house, the alarm finally kicks in.
It's 4:30 a.m. The doorbell jolts the neighbors from sleep. The girls stumble inside, breathless.
Rachelle Ebner: The first thing out of Taylor's mouth is, "Steve's at my house. He shot my mom and she-- he shot Tim and I think they're both dead."
Hoda Kotb: To hear that come out of a 12-year-old's mouth must've--
Rachelle Ebner: Yeah.
Hoda Kotb: --just been--
Rachelle Ebner: But it wasn't shocking. To me, it wasn't shocking. It was very realistic. I knew exactly that what she was saying was the truth.
Perry calls 911.
Perry Ebner: The kids were in the house. They said their mom's been shot. She's on the ground.
Taylor tells the operator what happened.
Taylor Lee: Hello.
Operator: How many times was your mom shot?
Taylor: Maybe two or three ... He got my mom's boyfriend too. I think he's dead ... He was just whacking bullets everywhere.
Taylor starts panicking about her brothers.
Taylor: I don't know where the boys are. We couldn't find them.
Hoda Kotb: Did you just want to make it all better for them, Rachelle?
Rachelle Ebner: Definitely. You know, it was really hard, because to maintain composure, it was just very difficult. I felt so bad because I knew they had just lost their dad. And I thought if the reality was that, you know, Teri died, that they would be orphaned. And that was very disheartening.
At 4:45 a.m., two cops are in position outside Teri's house. They can see Van Keuren's silhouette through the windows.
Police: I've got somebody walking around the inside wearing all black.
As Van Keuren paces inside the house, a SWAT team gathers. It's not fast enough for Taylor, who's worried about her brothers.
Taylor Lee: They're not going to catch him. They need to get here faster.
Finally police storm inside and disable Van Keuren by shooting him in the hand. They find the boys cowering in their bedroom closet.
At 7.10 a.m., Vicki receives the phone call she'd hoped would never come.
Vicki Swenson: And I have to tell you I was shocked.
Despite the no contact order, despite the top-of-the-line alarm system, despite the frantic calls to police, Teri and her boyfriend were dead, gunned down by the man who'd been stalking her.
Vicki picks up her sister's children from Rachelle's house and briefly talks to police at the crime scene.
Vicki Swenson: One of them expressed their condolences and he said "We just didn't see this coming."
Hoda Kotb: And you thought?
Vicki Swenson: I said "Yes, you did." I thought my husband was going to have to restrain me.
Vicki was determined to find out what had gone so wrong.
As savage and shocking as it was, Vicki Swenson says her sister's murder was no surprise.
Vicki Swenson: If I were a woman in an abusive relationship right now, I would think "Oh my gosh. Here's a woman who did everything right and she ended up dead. What does that say for the rest of us?"
Vicki says her sister's vigorous efforts to protect herself were stymied by an indifferent justice system.
She insists his bail should have been set higher after the knife attack. He only had to pay $7,500 in bond money to get out of jail.
Vicki: $7,500 didn't even come close to paying for her funeral. It's nothing.
She points her finger at local police who didn't arrest Van Keuren when he showed up at Taylor's volleyball game, which was a flagrant violation of his no contact order.
Vicki: I don't think she was taken seriously. It was very much an attitude of, "You'll be OK."
Bill Hutton is the sheriff of Washington County. His team handled the investigation into the knife attack.
Hoda Kotb: When you think about what Teri did, she was textbook doing it right. She called the police at the first incident. She had the no contact order. She installed an alarm system … and still this happened.
Sheriff William Hutton: Mr. Steven Van Keuren was very determined . And there was nothing or no one that was going to stop him
Hoda Kotb: We heard that Teri was told by an officer "Hey, look, you know, don't worry about it. He's just trying to get your attention." Would that be an appropriate conversation to have?
Sheriff William Hutton: That is the first time that I have heard that. So would it be appropriate to say it? Probably not. But it's the first time that I did hear that.
Doug Johnson is the Washington County attorney. His department pressed charges against Van Keuren after the knife attack, including two counts of first-degree burglary and one count of second-degree assault.
Hoda Kotb: Teri said to her sister that someone from your office advised her to drop the charges after that stabbing incident. Why would someone advise her to do that?
Prosecutor Doug Johnson: I think there's a misunderstanding there. There was no intention of our office to drop the case.
And what about that bail? The fact Van Keuren only had to post 10% of his $75,000 bail after the knife attack? It turns out the bail was actually pretty high for the charges Van Keuren faced.
Prosecutor Doug Johnson: I think that it was a reasonable amount.
Hoda Kotb: Even though she stood up in court and basically said, "I'm afraid he's going to kill me"?
Prosecutor Doug Johnson: I'm not sure how much bail we could have put on him. We asked for what we thought the judge would give us.
Hoda Kotb: Right.
Prosecutor Doug Johnson: He reduced that. You know, it's easy to second guess these things in hindsight.
Sheriff Bill Hutton is doing a lot of second-guessing. He was not in charge when Teri was murdered but he says his department is trying to be more aggressive now about pursuing men who violate no contact orders
Sheriff Hutton: We have more of a go-get-them attitude. And part of that is we will go and get you if you are a violent offender.
His officers did that just a few months ago, crossing over from Minnesota into Wisconsin to pick up a man who had violated a no contact order.
As Teri had suspected all along, local police could have crossed state lines to arrest Van Keuren after the volleyball incident but simply decided not to.
According to this incident report, an assistant county attorney advised local police it would be "best just to issue him a citation." In other words, the police officer should send Van Keuren a court summons in the mail.
Hoda Kotb: Why wasn't the advice "Just go arrest him; he's violated the no contact order"?
Prosecutor Doug Johnson: We didn't know where he was.
Hoda Kotb: But you don't think it would have been better advice, instead of saying, issue a citation and then start the ball rolling, just to try to track this guy down, since he clearly had violated the law?
Prosecutor Doug Johnson: Well, we can second guess and say, yeah, we probably should have done that. Maybe we should have.
What's more is that citation was never mailed.
Hoda Kotb: It was still sitting on the officer's desk after Teri had already been murdered.
Prosecutor Doug Johnson: Is there a question there?
Hoda Kotb: Right. I mean, that just kind of just shows the irony of the whole thing. There it sat.
Prosecutor Doug Johnson: There's a lot of irony here.
We wanted to ask the local police who had investigated the volleyball incident why they didn't arrest Van Keuren but they declined to talk to us on camera.
In a written statement the chief wrote "an internal review ... has concluded that police policy and procedure were properly followed."
In the end, the county attorney says there was really nothing law enforcement could have done to save Teri.
Johnson: There's only one person that could have stopped this murder and that was Mr. Van Keuren.
Hoda Kotb: But given that he was that kind of a guy, and everybody knew it, he was a guy who was going to do it, no matter what. Shouldn't extra precautions have been taken with him?
Prosecutor Doug Johnson: Well, the problem we have is trying to predict future behavior. Did anybody really predict that he was going to go in and kill her? Now, she said that.
Carla Ferrucci, Policy Director of the Minnesota Coalition for Battered Women, disagrees. She says research shows that women who tell law enforcement their lives are in danger, are usually right.
Carla Ferrucci: The biggest lethality indicator is when women say "he's going to kill me" and that's often the most ignored. And that's a problem.
Besides her questions about law enforcement, Vicki also had questions about the alarm Tim and Teri had purchased. It was supposed to be their back-up so they wouldn't have to rely solely on authorities, but it had not gone off when Van Keuren broke into the house.
Vicki has filed a legal claim against ADT claiming that the alarm wasn't installed properly. According to ADT, the system did not fail and was properly installed.
As hard as Vicki is battling to hold people accountable for her sister's death, she is also battling for a sense of normalcy for her suddenly enlarged family.
Vicki Swenson: Night time is tough. It's when we turn the lights off, we slow it down, we have time to think. I struggle at night and I know they do.
Where there were three, there are now seven children crowded around her dinner table -- and there's another one on the way, a little girl Vicki plans on naming after her sister.
The new family seems to be healing. Bed times begin with the same prayer the girls said the night of the murders.
Kids: Bless mommy and daddy and Tim and those that we love.
And continue with a tickle.
Both Vicki and Taylor, who just turned 13, have started speaking at events to raise awareness of domestic violence.
Taylor Lee: Domestic violence affects everyone. It affects men, women and most certainly children.
Hoda Kotb: Why do you think it's important for you to get out there and talk about this?
Taylor Lee: Well, if we don't tell people what's going to happen, who will? You're just going to let the story sit and just disappear? I think we should keep my mom living on.
Steve Van Keuren was convicted of first-degree murder in July and sentenced to life in prison, with no possibility of parole.
© 2013 NBCNews.com Reprints