Why Does My Cat Hate the New Kittens?

Kittens can make other cats aggressive
Benjamin Torode / Getty Images

Question: "Why does my cat hate the new kittens?"

Kathie has three adult spayed female cats and two eight-month-old neutered male kittens. Six-year-old Mindy gets along fine with the other adult females (eleven-year-old Addley and four-year-old Kia), but hated the two kittens Rhapsady and Karamel from the start when they were found at four weeks of age.

Kathie and her husband provide three large litter boxes in the basement that are cleaned daily, and feed the cats upstairs.

The kittens' appearance is the only change in the household, and the babies were kept segregated in a back bedroom for the first two months.

"We had Mindy checked by the vet and she seems fine--just overweight," writes Kathie. "Mindy used to get along fine with the other cats, now all she does is growl when any cat comes near her. I've had Mindy since she was a kitten, and she likes to lick and suckle my shirt since she was a baby. I don't understand why she has taken this "meanness" on the two new babies."

Mindy now growls at any of the cats/kittens when they come near her even if they are ignoring her. "We tell her 'No' firmly, no yelling and no physical movement, and she stops momentarily and then starts back up, and finally, she just gets up and leaves the situation. She spends a lot of her time away from everyone. I know she is a good cat. She was a perfect pet before the weight gain and the kittens.

She can be very affectionate sometimes and just walk up and butt heads with me. She even licks and purrs for me sometimes. I try to spend some special time with her alone every day, and give her extra loving and attention.
Amy's Answer

Mindy's dislike of the kittens can be purely a behavioral issue, caused by health-related and/or environmental concerns.

The H.I.S.S. Test can help narrow the focus by looking at the cat's health, instinct, stress, and symptoms. Your veterinarian may have eliminated all these possibilities, but I'll keep this response general to help as many readers as possible.


Your cat's weight gain made me perk up my furry ears. Although she's not considered "old" Mindy may have some arthritis issues going. Cats with painful joints tend not to exercise as much, and pack on extra padding as a result and then the extra weight makes it even more painful to move. Recent information indicates 75 percent of cats over the age of seven have arthritis. They hide it well, too, and simply stop moving quite so much. But pain can make kitty tempers short.


Cats instinctively feel suspicious of potential stranger danger, so when the boy kittens arrived, Mindy's reaction was normal. Remember that when Mindy arrived as a kitten, Addley was the adult already there. And when Kia arrived, Mindy was little more than a kitten herself. Kittens are much more flexible and forgiving of changes to routine, but now Mindy is on the brink of middle age and for five years had no "interlopers" to deal with. It can take months for a set-in-her-ways cat to accept a new pet, and proper introductions help.

Eight months in the scheme of things isn't all that long.


There's no easy way to say this: five cats may be too many. Every cat has a tolerance level, and Mindy's may have topped out at three cats. The greatest stress for a cat is another cat. Young kittens with high energy that pester, make noise, and disrupt Mindy's routine certainly could put her tail in a twist. On top of that, they're boy kittens so they act and smell different.

S=Symptom, Signs & Solutions

Bravo that you segregated the two kittens for two months! That tells me they were about twelve weeks old when they suddenly had full run of the house. As mentioned before, high-energy kittens this age might as well be a different species compared to a six-year-old fat kitty who may suffer painful joints and have trouble moving out of the way.

A growl is a warning to back off and can be either aggression-motivated or defensive. From your description of Mindy always ends up moving away, I suspect you may not recognize that the kittens' bullying. This is VERY easy to misunderstand. They don't need to be in her face hissing and spitting to antagonize her. When you shush Mindy for the growls, you're supporting them and telling Mindy the kittens are more important. That, in turn, tells the kittens they can get away with even more. Mindy's not being aggressive, but instead seems to act in a defensive manner, and has become so stressed she resorts to growls to keep all the cats (even her friends) at a distance. And as the senior to the kittens, she's probably feeling even more stress as she's no longer sure of her place in the household.

Cats that "come near" to Mindy are not ignoring her, even if they don't make eye contact-they're using the proximity of their bodies to make a statement and force Mindy to move from (I'm guessing here…) a favorite resting spot. So the first step is to start watching Mindy to figure out her comfort zone. Once you know the distance proximity to another cat that triggers her growls, see if you can shoo or lure the other cats away (especially the kittens) and keep them at a distance that doesn't prompt growls. Rather than telling Mindy to stop growling, try getting the other cats to back off. At Mindy's age, she should be in charge over the kittens and Kia at the least, and you can help her establish respectful boundaries. Use an interactive lure like a fishing pole toy or beam of a flashlight to get the cats out of Mindy's personal space.

I'd suggest increasing the resources in your home as well. If the other cats are crowding into Mindy's personal space, and perhaps coveting a particular sleep spot, why not double or even triple the ideal resting spot with lots of beds, cat trees, toys, and even boxes and tunnels to hide and play. If the kittens have more "legal" places to have fun, they should let up on pestering Mindy.

Although Kathie didn't mention litter box problems, I'm a bit concerned that only three are available and all relegated to the same basement area. With five cats, more toilet facilities wouldn't hurt. In fact, I'd strongly urge that at least one be provided on the upstairs floor.