Actually, as you have no outright fights, I wouldn't worry too much. I have a few who just can't stand the sight of each other and hiss every single time they pass.

I scan craigslist often, and frequently see folks asking how to introduce a new cat. I have a standard reply I send along, and I will share that with you. Your 2 have lived together for years so some of it won't apply to you, but I think some of it WILL apply. Hope you will find it a bit helpful!

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Hi!

Do NOT worry you can still work on things.

1. Be realistic. You can NOT make the cats best buddies. You CAN insist they live together with no fights. Set your sights properly and you won't be disappointed.

2. The cats will work out a hierarchy themselves. One WILL be dominant and it may not be the one you think or want to be dominant. Let them work it out. Keep a squirt bottle of water handy and interfere in any fights which get out of hand. Tussles, hissing, snarling are all normal as they scope each other out.

3. Start by keeping them separated -- different bedrooms with the door closed. This means you need water and litter box in each place. Do NOT let them be together unsupervised until you are comfortable they tolerate each other.

4. Let one out to be with you; return it to it's room and let other one out. Each needs time to get used to the other's scent. Let them sniff each other at the door bottom. After a day or so, swap their beds to they get each other's scent "in the face" so to speak.

5. I have 11 cats. I have introduced kittens and adults to cats living here. The fastest was 4 days. The longest was 3 weeks. So be patient and do NOT force them on each other. Let them progress at their own pace.

6. When you feed them, feed cat 1 first. When you pet them, pet cat 1 first. When you talk to them ALWAYS say cat's name to they get used to hearing the other cat's name.

7. Remember, cat 2 has to also learn the new home, sights, scents, routines, and adapt to YOU.

It CAN be done. There are MANY multiple cat homes. Just let things work slowly, and you will be happily listening to purrs in stereo in no time!