savgbeast
On my head, yet!
If they evolved into small excellent mice/rat exterminators, imagine them being domesticated like cats, with a Tyrannosaurus aisle at Petco and cute pet names like Ty or Mister Fingers and sleeping on the laundryBut the T-Rex would have had a lot of time to evolve, and with no pressure anymore from all the other dinosaurs who went extinct, it wouldn't make evolutionary sense for them to continue putting the resources into being so big. They'd probably be the size of toddlers by now, and they'd specialize in eating mice and rats and the occasional purse dog. Grandma wouldn't be on the menu, and she'd be no more at risk of a stray bite than she is from the stray peck of a pigeon she feeds.
I'm not that far away from old, and I would LOVE to sit in the park and feed T-Rexes when I retire. Maybe one of those biotech entrepreneurs will make it happen...