3 month old kitten appears healthy in every way accept that she seems to have suffered some damage to her hind end. Her front half is strong and normal but from the waist down she has very little motor control. When she stands, she trembles (up & down) like she has Parkinson's Disease. She is active and plays very vigerously but very often will attack (jump up) when playing with another cat, using mostly her upper body, she will very often "drag" around the back half. Her urination and stool appear fine, although sometimes I have noticed her anus protruding and a little red (she always goes in the litterbox). Her appetite, activity etc is great. Her top 1/2 is well toned, but her bottom 1/2 is not very muscular (particularily her legs). Any ideas how to rep this?