Any tips on integrating an adult cat? I have had a foster for a few months who had a broken patella, it was surgically repaired and I had full intentions of finding her a home just had to wait for her to heal fully as she was knuckling over on her leg. She has been in a large room in my basement for a couple of months. My dogs are just fine with her in fact she plays with my Ruby dog. Anyways hubby went downstairs to the room she was in yesterday and when I got home from work told me that I should let her out to wander around. A couple of my cats have smelled her through the door etc in the past. She could care less that my cats are hissing at her, there haven't been any fights but they are guarding the stair way and not wanting to let her upstairs, they hiss at her. She hasn't hissed or anything at any of my cats. She's very laid back. She is about a year and a half old or so maybe a little older. My cats are 8 months to 15 years old.