Introducing a New Kitten to Older Cats

How Can I Introduce New Kitten to Older Kittens?

Ginger kitten cuddle with adult tabby cat.
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Question: "How can I introduce a kitten to older kittens?"

Jay writes, "Hi Amy, Please do help me out as I am troubled by three kittens. I got Coffee and Ice Tea from the street around the tender age of one to two months. They are now healthy and active five to six months kittens. Four days ago, I found another poor little stray, and brought Furry home. Since she was already wet, I bathed and dried her before giving her food.

Furry was threatening the first few hours and I had to put her in a cage for the first day.

Once Furry was calm with me-purred when I stroke her and fell asleep in my arms-I tried introducing her to both Coffee and Ice Tea, but that went very bad when I tried to place her on top of Coffee/Ice Tea. Both of them tensed up, ears flattened and they keep hissing at the first sign of Furry. No physical attack or threat has been made so far, just hissing. Now when I try to hug or carry Coffee and Ice Tea, they turned stiff.

At the moment, Furry's room door is closed and Coffee/Ice Tea door is open but they won't come out. They aren't as playful/affectionate as before. I cannot leave all three of them in the same room unattended, I am afraid that they will hurt Furry, but I really do hope that they can go along. What can I do to bond them? a friend of mine suggested to bath them all three together, is it okay doing so?

Amy's Answer

Hi Jay, aggression during introductions is very common among cats. I know it's taken some time to answer your question and by now, I expect the cats are older and doing much better. But for future reference, and for other readers, I'll answer - and because your kitties are adorable! Of course, veterinarians and behavior specialists look at the cat's physical and emotional health, as well as traits of instinct to help figure out what's going on and find solutions.

Think of this as the ​H.I.S.S. Test, which stands for health, instinct, stress, and symptom solvers.

H=Health

It's very important that you have a new kitten or cat examined by a veterinarian before introducing to the resident kitties. Even healthy looking felines may harbor hidden diseases that could make your resident cats sick and that might even be one reason the older kitties object to the newcomer.

I=Instinct

Cats dislike change. So rearranging furniture or changing the litter or introducing a strange cat all can get their tails in a twist. Familiar means safe in the cat world, while stranger = danger.

S=Stress

Simply the stress of any change, of Furry being on her own outside, or of you paying attention to Furry instead of Coffee and Ice Tea could raise the stress level.

S=Symptom, Signs & Solutions

Before anything else, BRAVO that you rescued Furry. She surely would have died had you not brought her into the house off the street.

There are a few missteps along the way, though. Your friends actually are correct that bathing all the kittens with the same kitten shampoo--not all at once, though--might be helpful because it would make them all smell alike. Cats identify their family by the familiar smell-Coffee and Ice Tea sleep together and groom each other so they smell alike.

But Furry smells different and therefore is suspect. Making them smell alike simply by rubbing all the kitties one after another with the same dry towel is a better option that risking life and limb bathing reluctant cats, though.

At the time you wrote, Furry had only been with you four days. Cats may take four weeks OR LONGER to accept a new cat into the house! I suspect/hope that you didn't literally mean you "placed her on top of Coffee/Ice Tea." I'd throw a hissy fit, too! Imagine having a stranger you don't know suddenly arrive to sit on your lap?

Separating them into two rooms is a very good first step. There is a detailed step-by-step plan for cat-to-cat introductions in this article, and I urge you to refer to that in future cases of kitty introductions.