Cat Suddenly Hissing
I have 2 male cats, Max and Sonny. Sonny recently spent 3 days in an animal hospital for a severe bladder infection, and now he is home and doing much better. Max, the older cat, has suddenly started hissing at Sonny and acting very mean toward him. This is very strange, because before Sonny's illness they were best buddies who cleaned each other and slept wrapped around each other. Sonny has tried to be affectionate with Max, but Max keeps hissing at him and batting at him with his paw. I can't understand why Max's behavior has changed. If anyone has any ideas I'd really appreciate it! Thanks!