Thanks for your reply, your problem is really close to mine. Here is what I ended up doing, maybe you can grab a few tips for yourself.

I kept them separate for 5 days total. Each locked in a separate room with food, water, liter. The family took turns visiting with each cat a few times a day, but kept them separated.

While the agressive cat was locked up, we would let the "non-agressive" cat out to roam around the house. We did this 1-2 times a day. On the 4th day we reversed that, keeping the non-agressive one away while the agressive one roamed the house. During the day they each had their own blanket and at night we switched blankets so each cat would get the other ones scent. On the 5th day we fed them together in the same room with no problems. For the past 2 days they have been let out together and they seem to be getting along. I am still going to separate them at night for a while just to be sure.

[ Show Entire Thread ]