Thanks, that is definitely good to know your experience with this! I see so much varying info on mixing FIV+ and negative cats, and even my vets said different things. I will put Tab in the cage to start out with, but he's pretty mellow and not so young any more, and I had him neutered before I gave him to my friend. My Siamese cat, Koji might even remember him, though it's been a few years since they knew each other. Tab is real sweetie, so I think they'll all get along fine.