New Cat & resident cat not getting along

[MidoriLewis]

We got my resident cat about 3 1/2 months ago from a shelter, she is about 2. She loves all people and it only took about 20 minutes after we brought her home to get used to us, cuddle with us and get used to the home. 3 days ago we brought home a new, 6 month old rescue. It took a day for her to get used to us, now she is cuddly and loves being with us. The first day our resident cat would not come down from her cat tree because of the new cat. Since then, our resident cat constantly hisses at her when I bring her out of our bedroom. The new cat won’t come out from under our bed during the day unless we come into the room to greet her, but as soon as we leave the room she goes back under the bed. Our resident cat was only hissing at her for the first two days but yesterday was the first day she actually went to attack her. I didn’t let her get the the new cat so I’m not sure if she would’ve hurt her or not. Ever since that attack the new cat has been extra scared and the little roaming she would do around the house during the day, she no longer does, unless we close the door to the bedroom. (Which is her “safe space” with food and water etc.) I have since then bought 2 Fleiway diffusers and give my resident cat natural calming pills at night so we can bring the new cat out to roam a little under our supervision. At night, when I’m sleeping the new cat and resident cat are both pretty active, I don’t know if they have any actual interaction but I have woken up and seen them both walking around the house. How long should I let her hide in fear and let my resident cat hiss and bully her into being scared before considering giving her back to her foster home?

P.s. I know you’re supposed to slowly introduce them and lock the new cat into a room and introduce their scents but I didn’t know that when I got her, and when I tried to lock her in a room after I learned all of that she got really sad and all the progress we made with her for her to trust us, and let us pet her went down the drain, so I’m not doing that.

 

[Furballsmom]

Hi!
Take a look at these articles - these are tried and true methods;
How To Introduce A Kitten To An Older Cat – TheCatSite Articles

How To Successfully Introduce Cats: The Ultimate Guide – TheCatSite Articles

How To Fix An Unsuccessful Cat Introduction – TheCatSite Articles

I have woken up and seen them both walking around the house.

Due to this...

giving her back to her foster home?

...I wouldn't consider this at all

 

[Remi&RiRi]

Hi! So its only been 3 days which is really nothing! It usually takes 2-3 weeks for most cats to get fully used to each other and sometimes can take a month or so just for them to be civil. Definitely give it more time and take it slow, you are most likely to have success by following the introduction steps. Even if its slow progress, it's still progress. When I introduced my adopted female cat to my resident male cat, I researched all the steps of cat introductions and was willing to take it slow. I told my partner about the steps but he thought it would be fine to just let them have access to each other after just a couple of days (which sounds similar to what you have done). I think the excitement got to us both and we rushed it. Like you, as soon as we did that the cats started having little spatz. We had to do the reintroduction process three times with our cats and eventually we felt comfortable enough letting them have access to each other but things still weren't perfect. I know it can be hard to leave your new cat in a room and it may feel like things are going backwards but the new cat really needs to have time to adjust to each space and feel confident room by room before it can feel comfortable getting to know a new cat. Just make sure you spend time with your new cat (play or let the cat come to you) and also make sure you have its food, water, and litterbox in the room! Its been about three months since bringing our 2nd cat into our home. Things have improved greatly but the progress has happened very slowly. They rarely get into any spatz now and will now sniff each other and even nap just couple feet apart! Sometimes cats never become ‘great friends’ but as long as they are able to safety be around each other, thats all we can wish for. Some cats personalities just mesh better than others. A little clawing, growling, and hissing is bound to happen but it should hopefully keep happening less and less, just always make sure there are never any injuries. It may take several months but they should acclimate with time. Best of luck and keep us updated!

 

[rubysmama]

Hello and welcome to TCS. As you now know, it's almost always necessary to keep a new cat/kitten separated from the resident cat when you first bring it home, and slowly do introductions.

Since it's only been 3 days, I think the best thing would be to put the kitten back in a separate room (even though she doesn't like it) and start the process all over again. Otherwise the bullying may continue, and lessen the chance of them becoming friends.

One of the things we always tell people to watch for when introducing cats, is one appearing to be scared. Now if they are playing, and it gets a bit rough, and the kitten runs away and hides, but quickly returns for more "fun" that's fine. But if she is hiding and really looking scared, then you need to separate them and start again.

Your cats are not the first to have an unsuccessful introduction, and TCS even has a article on the topic:
How To Fix An Unsuccessful Cat Introduction | TheCatSite

We also have one on Are My Cats Fighting Or Playing? | TheCatSite in case you're not certain if they are playing, or if your older cat is being aggressive.

Once the kitten is back in her own room, spend lots of time with her. And you can still put the older cat in a closed room for a little bit, and let the kitten have full run of the home. Just keep them separated, until you're certain they won't get into a fight.

Good luck. Hopefully in time they'll be best buds.