Wow! HOw lucky you are I think it does have something to do with the type of coat a cat has. Like Pam, I have one cat (Marius) who has a really sleek, close lying coat, and then I have Scooter...who is also a short hair, but has really thick fur with an undercoat. I have seen Scooter upchuck hairballs so much more than Marius...although Marius isn't totally hairball free...but he just doesn't do it as often! LOL