Laura, Storm had the same problem as your Giz and he also scared me but he was able to pass a large stool even though he was in a lot of pain. I e-mailed my vet about it and she just said to give him hairball medicine,Petromalt, at least 2 times a week. So far this has done the trick. If she still ends up having a lot of problems then she may need to be put on lactulose daily. My RB Pepper had to take this and it sure helped him. Good luck.