Welcome to PT, Jasper and Pyro! (Notice who got first mention. LOL) I have nothing to add to what's already been said other than to introduce the cats to each other gradually, for a few minutes at a time, each day. They can be like people and not take to certain cats no matter what. I had that situation in my household for quite some time and, as long as the two of them steered clear of each other, all was peaceful. It eventually rectified itself and they were able to peacefully coexist. Just be sure to always be in the room w/them when you put them together; don't leave the room thinking that all is well. Good luck, keep us posted w/some pix (hint, hint) and bless you for not turning your back on Jasper.