Lorraine, I'm sorry to hear that you're having problems with your boys. I think that Jen's suggestion is a good one and I'd try that first.

Even though all of my cats get along very well, Storm can still be quite stormy towards both Sunny and Sky. Lately he's been chasing poor Sky around for no reason. I just think that he's getting grumpier in his old age and won't tolerate as much as he used to. He loves the girls though so maybe you need another girl in the house. Good luck.