I have 3 cats. Julian who is 7 years old and and Rocky & Thumper who are 3 years old. For three years they all got along great.Then this past weekend all changed. I don't know what happened but Julian now hates the other two. (Thumper more so) He spits and growls then runs and hides under a bed when he sees him. Which it turn makes Thumper chase after him. The worst episode was Saturday evening, Julian was in the kitchen and Thumper came in. The sounds that came out of these cats were so scary. My husband and I have since seperated them. Julian is fine with us but soon as he smells the other cats near by he starts to growl. We called the vet today. He says to isolate them for two days. If it's still happening after that he will come up with an alternative. I'm very worried. I love my boys. Any ideas???