Hi everyone, I'm writing for my brother, he has 3 cats, all neutered or spayed. 2 males are about 4 years old, he adopted them together as kittens and they've always gotten along great, grooming each other, sleeping together, etc. They were like best buddies, it was heartwarming to see them together. His third cat came along as a stray about 2 years ago and after a brief initial period of hissing and swatting she seems to have been integrated fine into the family. In the last month or so the behavior of the males has changed, they no longer get along and do a lot of hissing, chasing and what looks like real fighting till he breaks them up by yelling at them. So far no blood. The female remains detached from the action and just looks on from the sidelines. Also, one of the males has taken to spending most of his time (when he's not scrapping with his housemate) in an upstairs bedroom where he cries loudly and long. Also, the one crying one seems to be on the receiving end of most of the aggression, not the instigator. It's like his friend suddently rejected him and now hates him, so he is miserable. I told him to start by taking that one to the vet. None of them show any obvious signs of illness, no weight loss, food or litter issues, etc. Just the sudden hostility and crying. My brother said he would call the vet but in the meantime does anyone have any ideas? Thanks in advance, Andrea