How to Introduce an Adult cat to a new kitten

A common scenario when you Introduce an Adult cat to a new kitten

When you decide to introduce an Adult cat to a new kitten in your home, it’s usually more exciting for you and your family than it is for the cat you already own.  Although most cats are solitary by nature, most will also come to accept or eventually tolerate any additions.

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When my Siamese cat Jasmine passed away from kidney disease in May of 2021, we were all devastated. Anyone who has lost a furbaby understands how they are family members that are loved and adored. After her passing, our surviving cat Jewel, a 9-year-old Ragdoll, would not go near the areas where Jasmine last laid for about 3 weeks. She also grieved, just like we did.

siamese cat posing

As the weeks passed, we showered Jewel with love and attention, but we felt she was feeling lonely. Jewel is a very skittish cat by nature. It took me 4 months to rescue her from the neighborhood pack one Spring years ago. Once she was rescued, she used to hide under the bed and only come out for me. She has since socialized fairly well and used to follow and play well with Jasmine. But the time has come to introduce her to a new cat for companionship.

ragdoll cat Jewel with blue eyes

When is it time to bring in a new cat?

This time, the table has turned. Jewel is the one with her scent around her home who must adjust to a new friend. As any cat lover knows, cats are extremely territorial. A published study in 2013 found that domesticated cats share an astounding 95.6 percent of DNA with the Amur tiger. Tigers are solitary animals by nature, although, mothers and offspring tend to hunt together. Lions, by contrast, are hunters in groups known as a Pride. I feel our housecats tend to take on preferences of either a pack cat or a loner with the ability to tolerate a smidge of both.

We often ask, when is the right time to introduce an Adult cat to a new kitten. The bottom line is, there is no solid answer. Both humans and the surviving pets need time to grieve and adjust. We also look at our home life. Sometimes we work from home, sometimes we are at the office.

 Based on the personality of our existing cat, are we nearing the time to find her a friend? Let us be honest, it is not only the humans who enjoy our cats, but does your cat thrive with another furry friend? These are the questions to ask yourself when considering when the proper time is to adopt another cat. Remember, cats can be very territorial, which is why you should always be careful when you introduce a new cat to your current cat.

The Arrival – time to Introduce an Adult cat to a new kitten

If you are introducing kittens to one another, the entire introduction process can be short, lasting as little as 10 – 15 days.  Introducing cats to each other all depends on their temperament and their personality. If you do not have an existing cat, you may want to consider adopting siblings, which will make the transition easier to a new environment.

When you introduce an Adult cat to a new kitten, you should always make sure that you give your current cat plenty of love and attention.  This way, your cat will feel secure and know that they are not in competition with the new one for affection. I made it a point to spend one on one time with Jewel after bringing home Marco, our new Tuxedo 4-month-old kitten. I showered Jewel with love and affection before bringing in a new cat, and immediately after.

tuxedo cat
Marco 4 months old

When you bring your new cat home, you should let them stay in a safe room until you have finished introducing the cats.  Your safe room can be any small room in your home, such as a bathroom or spare bedroom.   The key here is to use a room that your current cat does not go in.  In the room, you should leave your new cat a scratching post, bed, water dish, litter box, and food dish.

All the experts will agree this is the most appropriate way to transition a cat to a new home. We, however, bent the rules a bit. Read on to see what happened.

What we did

We placed a litter box in the adjacent bedroom and closed the door to the hallway. Then, we placed cat toys, a cat bed, scratching posts, food, and water in the bedroom. Our current cat saw us enter the home with the kitten in the carrier, and she remained upstairs after hissing once she saw the threat.

We kept Marco in that room the first two days, allowing him only access to the bathroom where his litter box was kept. We made sure we continued to interact with Jewel, but she knew something was up. Most cats do not like closed doors. The only doors in our home we consistently keep closed are closet doors. All the other rooms have open access. Having a closed-door was upsetting to Jewel. For this reason, we sped up the introduction process.

introducing an adult cat to a new kitten

What happened next

If you are following the recommendations to house the new cat in a separate room, it will be normal for your current cat to howl and hiss when they stand at the door. They are trying to tell the other cat that they do not belong.  When this happens you should ignore it, as punishing your cat for their behavior will only lead to more problems.  After a while, some cats will start to act calm when they are near the new cat’s door.  As they start to act calm, you should pet them and give them praise. Unfortunately, we never made it to that phase.  As I said, Jewel does not like closed doors. She meowed and clawed at the door incessantly. To save our door, we let her in and the introduction was on.

The Rule of Paw (thumb)

When your first cat starts to go by your new cat’s door and doesn’t howl or hiss; you can start introducing them to each other.  The best way to do this is to get them used to each other’s scent.  Some cat experts will recommend letting them eat out of the same food dish, although feed them at different intervals at first.  This way, the scent of each cat will be present at the food dish, and each cat will get the scent when he eats his food. You accomplish this by using the same dish at different times in different rooms.

Once both cats have gotten used to the scent, you can begin to feed them closer together.  To do this, you should keep your new cat in the safe room with the door closed, and your first cat on the other side of the door with their food dish.  This time, feed both cats at the same time.  After doing this a few times, they should start eating without any hissing or growling.  At this point, they are ready to be introduced to one another. Read on to see how our introduction process actually worked.

The Meeting to Introduce an Adult cat to a new kitten

It is the moment you have been waiting for – the actual face-to-face meeting! When you introduce them to each other in the same room, a bit of growling and hissing is to be expected.  Although they may be used to each other’s scent by now; your first cat will still feel a bit awkward with your new cat being in his territory.  You should play with them both at first, so they can smell one another and greet in their own way. If they start to fight you should break them up and give them some time apart.

Here is what happened when Jewel met Marco in our house.  After 3 days, we decided it was time to introduce them. We bypassed the above sharing of food dishes that are supposed to start the scent introductions. Our timeline was shorter than recommended.

We opened the bedroom door and Jewel slowly walked in. As soon as Marco saw her, he ran over to pounce and play. You see, Marco had 4 other siblings and was used to rolling around and playing. Jewel was not expecting this and immediately ran under the bed, hissed, and growled. Marco had never been exposed to that behavior and was not sure what to do. What we learned was, it is not just the original cat you have to think about, but the adopted cat as well. Was it used to playing with others? Was it happier playing solo? Marco was very social and obviously wanted to continue playing with others.

The Meeting Plan B

We decided to monitor the cats but did not separate them. Jewel did not want to leave the room and Marco was too excited to meet her and wanted to stay and watch her. As a result, we stayed in the room and talked softly to them both. Jewel was used to us talking to her, so we made sure we spoke softly and reassuringly.

We also grabbed some cat toys and lured Marco away from Jewel when she seemed too stressed. We could tell by the loudness of her growling. As much as we could, we continued to play with Marco and let Jewel watch from across the room. We all stayed in the room for the next 2 hours. Neither cat wanted to leave the room. They were completely engaged in watching each other. Marco continued to creep up to her to test the boundaries, then would turn around and play. Luckily, he really liked playing with the Catit Design Senses Circuit cat toy that we bought a few years ago. It’s an oldy but goody!

How long does this awkward period last?

There was no magic moment when they started to tolerate each other, or rather when Jewel started tolerating Marco.  It may take some time to get your cats fully used to one another, although once they do – they will become playmates for life.  Most cats do love to be social, although it may be a bit rough at first, especially for your original cat. 

Cats can be very territorial, so it is important to continue to play with your first cat in their own personal space too, without the new cat around.  If your first cat recognizes there is no threat and is just as loved, it will help them feel even more comfortable.

Moving forward, do not expect your cats to become best buds after only one week from the introduction. They are on their own time, not on yours. Depending on their personalities and comfort levels, it could take months or longer for them to have complete companionship. Give them time, love, and equal attention. I hope you now feel more comfortable and ready to introduce an Adult cat to a new kitten.

To learn more about kittens, how much to feed them and everything else new kitten-related, refer to beChewey for their information.

Good luck with your new household!


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