Has he been checked for fleas? My cat Leonardo took to pulling his hair out over his tail several months ago. His vet said they do that when they have fleas. There were no signs of fleas on him though. He has allergies too which his vet finally decided was the reason for his hair pulling. She shaved all the hair off his rump and gave him some anitbiotics and that cleared him up. A trip to the vet will be your best bet. It could be lots of things. Maybe even the stree of going through all the stuff with the jaundace. Sorry, I guess this wasn't much help. Please keep us posted on Peterson's progress.