Just outside New Orleans, while neighborhood kids play in the schoolyard at Estelle Elementary, 5-year-old Jamond Robinson is stuck at home. He was kicked out of school last month, escorted away by police after biting a teacher.
"When he gets mad, he just hits, bites, kicks, spits," says his mom, Monique Synigal.
Monique says Jamond was well-behaved before Katrina hit. That was before he was forced to squeeze into a cramped home with 10 relatives.
"When we came back (after Katrina) to see part of the house, he was crying," remembers Monique. "He lost everything. Katrina took his toys."
Grief, depression, violence — they are alarming but familiar symptoms to pediatrician Corey Hebert, who recognized them and diagnosed Jamond with post-traumatic stress disorder, PTSD.
"There was a natural disaster, then a manmade disaster, and now we're having new cases of a whole new disaster," says Hebert.
So far, no study shows how many children are suffering emotionally after Katrina. But following Hurricane Andrew in 1992, researchers found 40 percent showed significant signs of post-traumatic stress.
Post-Katrina, some children who lost homes or loved ones still have flashbacks and nightmares.
Stacie Blanchard's 4-year-old son Briley hasn't been the same since their evacuation. "When the weather is bad, you know, he's back in bed with us," she says.
"If they don't get any help, those are symptoms that can follow them the rest of their lives," says Dr. Russ Newman with the American Psychological Association.
Three-hundred-and-fifty miles away in Houston, young Katrina evacuees are working to rebuild their self-esteem through exercises at school. A wide range of programs, including art therapy, help them focus on hope, not hurt.
"It's fading away, but it's never going to be gone," says evacuee Paige Nicolette Dillon.
As for Jamond, he's now enrolled in a new school.
More than six months after the storm, Katrina's youngest victims are still struggling to regain the childhood they once enjoyed.