UPDATE: Thanks to everyone!
As Cali is coming off her Dilantin, I feel that her legs are getting looser (if that's a word, LOL). When she flexes the back legs, they are really stiff. But when she relaxes them, they feel really loose. I think this is a good thing.
Next up: blood draw on Saturday. Hopefully my vet will change her food to a hi-cal option. Then Monday she starts PT!