Jessica Rico says her father Guadalupe was last seen Saturday.
She says his truck was stolen and found abandoned by the loop in southeast Houston.
A store owner told her a man not matching Guadalupe's description was trying to sell the truck, but no one would buy it because he didn't have the title.
"I don't want to think the worst. I have faith that he's still out there. I don't know if he's safe, but by the looks of it, when we did recover the truck back, the truck does have blood specks on the driver's side," said his daughter Jessica.
Jessica says her father has medical problems and can't walk very far on his own. She says he's a dialysis patient and is diabetic. He needs frequent dialysis treatment and is on daily medication for his other conditions.
If you've seen him, call police.