This has been going on for three months now, done all the right things, male 8 yr old checked out ok at vet with urine samples and bloodwork. Kept him separate from other 3 cats (11 yr, 1 yr & 6 mos) in spare bedroom, started using litter box again. Got Feliway diffusers, the spray, even have the calming collars on all cats. So, after a week of using litter box, decided to let him out and what does he do? Starts spraying again, even before seeing any other cats (they're downstairs). When he did see the others, the 11 yr old hissed like she's never seen him before, the other two ran. Then he got an attitude with me, acting like he was going to attack me. I carried him back to the bedroom. Is it time to get rid of some cats and if I do, will he still continue to spray? Can I keep him in the spare bedroom the rest of his life? The other cats are fine until they see him and he is fine until I let him out of the bedroom. I've tried suggestions from numerous articles to help him.