01/31/2013 at 10:00 AM EST
Austin Mobley was just 6 when his mom, Tracy, asked if he knew the owner of a black-and-white dog running around their yard. "Mom," he said, laughing, "that's Daisy," their longtime family pet.
Twelve years later, Austin cooks, balances the checkbook, drives Tracy on errands from their two-bedroom apartment in Buffalo, Mo., and manages his 48-year-old mother's medication for the dementia diagnosed when she was 36.
"The hardest thing for me," says Austin, 18, "is not knowing what an actual mom is."
Every morning the high school senior rises at 6:30 a.m., makes sure his mom takes her meds – Namenda for dementia, Valium for paranoia, Prozac for depression – and then gets a ride to school.
After school, he heads home, does his homework and gets to his other job – paying bills, picking up around the house and helping Tracy cook a dinner of spaghetti, steak or pork chops.
At night, he makes sure Tracy settles under a blanket in a recliner and gives her a bedtime hug; she keeps the TV on all night because it soothes her.
That's on a good day.