A nationwide search was on Thursday for a 15-year-old boy and his 13-year-old girlfriend, who fled their homes with one family's minivan, $680 in cash and a dog named Mandy.
Authorities believe they may be bound for Colorado or California but did not elaborate.
Gage Petherbridge, 15, and Hannah McConnell, 13, left notes and journal entries saying they were running away together, according to their mothers. They live in Vienna Township, about 65 miles north-northwest of Detroit.
Mary Wismer told The Flint Journal she woke up Saturday morning to find her son, her minivan and his cocker spaniel gone. She said her son also took clothing, food and his Xbox 360 video game system.
Soon after, police arrived and said Hannah's parents had just reported her missing.
Wismer said her son, who is in the first year of high school, left a note apologizing and promised to call. He had not done so by early Thursday, The Flint Journal reported.
"My son is very much in love with Hannah," Wismer said.
Julie McConnell said she worries because her daughter, who is in her last year in middle school, has bipolar disorder and left without her medicine.
McConnell said Hannah took $100 from her purse when she left, and Wismer said Gage has about $580 in cash he got for Christmas.
The minivan is a white 1997 Pontiac Montana with Michigan license plate number 6DYW54, the Journal reported. Anyone with information is asked to call the Genesee County Sheriff's Department at (810) 257-3406.