Our experience introducing two cats (adult and senior)

Hello folks! Longtime lurker here, and reading posts on this sub was incredibly helpful when my partner and I were preparing to introduce our two cats. For us it was a very long process, but that time was really needed. I thought I would share our experience here, since I personally found the posts folks made about their many-months introductions to be a huge encouragement went I felt like no progress would ever be made. I hope that this post will help others in the future!

So to set the stage, the two cats in question are Andie and Wendell. We both adopted our cats while we were single, long before we met each other.

Andie is my partner's cat, and she is at a minimum 14 years old (shelter estimate), adopted in 2017. She is petite, incredibly sweet with people, and though a bit reserved, warms up to marathon-length lap sessions. She has historically been fine around other animals (dogs, rabbits) but did not like being with other cats at the shelter. Andie is also an extremely picky eater, and not food motivated at all. This was a concern for us going in, as so many introduction guides (understandly) say to use treats as a motivator.

Wendell is my cat, and he is alleged to be 10 years old, but I would actually guess a little younger (again, his age is a shelter estimate). He was adopted in 2019 and is in many ways the complete opposite of Andie. He is super vocal, quite large (not fat just a long boi), and very playful. He too is very sweet with people and loves to cuddle. At the shelter, he was with other cats and was fine with them. I knew he did not like dogs, but had no clue what to expect for fellow cats. But thankfully, he is food motivated and will be easily lured by treats.

Before we moved in together, we spent a few months preparing everything to make the cat introduction process as smooth as possible. This included changing Andie's litter so that they both used the same kind (familiar smells), introducing feliway friends plugs in both our homes (though ultimately I don't think it helped), and getting Andie accustomed to a microchip feeder. I mentioned earlier Andie is picky - she is a grazer and refuses to eat on a schedule. We knew Wendell would gobble up all her food if given the chance, so this feeder was a must for us. My partner is very handy, so he made a cute acrylic box for the feeder to be placed in to make sure Wendell couldn't steal any from behind (the backing that one can purchase for those feeders did not look substancial enough to us).

On the day I moved in to my boyfriend's place, my mother very kindly agreed to stay at my old place with Wendell for the night, so that we could focus on unpacking and preparing the space. This was a huge benefit to us, as it meant that in addition to a new environment, Wendell wouldn't also be dealing with loud noises. The first day we unpacked eveything that went in the main and second bedrooms, and both bathrooms. There was still lots of work to be done in the living room and kitchen, but we knew that with both bedrooms and bathrooms ready we would be able to begin the introduction process. I headed back to my old place the next morning, and picked up Wendell.

As you'll find recommended everywhere, we kept Wendell to one room (second bedroom) at first. He is naturally a pretty confident kitty, so we knew we wouldn't need to keep him in one space for too long. During the first couple days we would hang out with him in there (together and separate), and intermitently give him some alone time. Because he is so vocal, Andie figured out very quick that there was another cat behind the door. Wendell, bless his heart, took ages to notice Andie's existence hahahaha. One more thing we started doing during this time was put towels on their beds, and swap them each night to get them used to one another's smell.

Once Wendell was ready to explore outside the second bedroom (after about a day), we slowly introduced him to the rest of the apartment, but never with Andie in the same room. Over the next few days, we did "site swapping" every few hours, rotating which cats were in which room, so they could smell but not see eachother. It was on day 2 or so of siteswapping I think Wendell finally realized another cat lives in this home. We called the process of swapping them around the "air lock" since we would take a cat into a bathroom, wait for the other person to holler that their cat was successfully moved, and then let them out.

At this time we also started what would become our nightly ritual for a few months, swapping which cat was in our bedroom every night. After a few days of the site swaps/air lock, we felt we were ready for limited contact through at obscurred gate. My handy partner made a superflexible, perforated, metal sheet we clamped onto the bedroom door, with allowed us to easily get in and out but keep the cats from mixing with eachother. At first we used a towel on the gate as well, just so that we could better control how much the cats saw of one another.

To the best of our ability, we tried to use meal times and food as rewards during "door time" as we came to call it. This was again a challenge with Andie, but thankfully Wendell's hesitancy about seeing Andie would melt away the moment we put a churu tube in front of his face. All in all, we spent three full weeks with the gate up, doing bonding "door time" two-to-four times a day or so. Over those weeks Wendell warmed up tremendously, going from the occasional hiss early on the flopping over and happily exposing his belly to Andie. We assumed going in that this introduction was going to be on Andie's timeline, not Wendell's, and door time really showed that was the case. She did eventually start eating (several feet away but in sightline of the door) with him present, and that's when we knew we could begin the next phase of controlled time together in the same room.

To start, we would wait until Wendell would fall asleep in a given room, and then open up the door to wherever Andie was and let her come in. She was wary when she would see Wendell, but since we did this when he was deep into a nap she started to trust us that it was safe. Once Wendell would start to stir, we would separate the cats again. We took the adage "always end on a high note" very seriously. After a couple weeks of Andie growing more comfortable being in the same room as Wendell (and continued door time when they were separated), we graduated to letting them be in the same room with both cats awake, but separately engaged. This meant playtime for Wendell, laptime for Andie. Eventually we could get to the point of having both cats close to one another, without even being on our laps. That was definitely a huge milestone for us, and at that point I had been moved in for nearly three months. I just want to again emphasize that Andie needed us to take things very slow, and that's what we committed to.

There were definitely times where I felt in dispair, like we would never make progress. All this time we had been keeping the cats separated when we left for work (each with access to a litterbox, their food, and two water dishes), and in many ways I was concerned we were never ever going to see real progress. But one thing that helped a lot was to read over old messages and look at pictures from the weeks and months prior, and that really showed me just how far we had come. Andie had gone from being scared of Wendell, to mostly just annoyed with him. Sure, she would hiss if he got too close (or give him a little bap for good measure), but she wasn't running away to hide. Our big breakthrough came around Christmas, a little over three months after moving in, when both cats could sit next to eachother on the couch without incident. This was when we decided we were ready to stop our nightly cat swapping, and let them both have free roam of the apartment overnight.

We got into a good bedtime routine. We would do Wendell's wet food right before bed. Wendell would eat in the living room, and Andie would be in the bedroom with us while we brushed our teeth and put on PJs. Usually after around 30 minutes or so, Andie would tuck herself into bed in her favourite sleeping spot, her cushion on top of the dresser. Once we settled in, we would open the bedroom door so that Wendell could come in if he wanted to. I don't know if it's good training or pure dumb luck, but Wendell never hops up on that dresser to bother Andie. To this day, this remains our bedtime routine.

While we still keep the cats separated if we are going to be out of the house for a long period of time (like the workday), we no longer need to worry about them being on their own in the same space for short periods of time while we go out for dinner, to run errands, etc. We've kept the time apart during the day because Andie seems to really like having those few hours to herself. Wendell just naps when we aren't home, so he isn't bothered by not having company.

These two sweet kitties will never be best friends. They don't snuggle, they don't groom each other, and Wendell does still annoy Andie by wanting to play with her (she isn't interested lol). But they happily coexist, which we considered a success as far as cat intros go.

To everyone who has ever written up their experience introducing cats, thank you. I swear we read every single one of your posts. If anyone from the future is reading this now and found it helpful, please consider paying it forward by doing your own write up when your introduction is finished.

TL;DR introduction timeline

- Day 1 | new cat in second bedroom to get used to new environment

- Day 2 - 3 | site swapping so cats could smell but not see eachother

- Week 1 - 3 | "door time" feeding rituals, through a semi-obfuscated barrier

- Week 3 - 8 | slowly increasing cat time together in the same room, but without interacting with one another

- Month 3 - 8 | cats could be in the same room together without issue, roam the apartment overnight

- Month 9 (present) | two sweet kitties that coexist

Cat Tax: embedded throughout the post, but here's one more!