Get

In Your Inbox

Catster is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

I Just Got a New Kitten & My Older Cat Hates Them: 6 Vet Approved Tips on What to Do

Angry,Calico,Cat,Lying,On,Edge,Of,Bed,Wagging,Tail

Bringing home a new kitten can be stressful not only for your new addition but for your existing pets as well. There is an adjustment period that should be expected with the addition of any new pet to the home, but you’ll need to take steps to make this period go as smoothly as possible. It is not uncommon for older cats to react negatively to the addition of a kitten to the home. It can feel like your older cat hating your kitten is something that will never end, but there are things that you can do to ease the transition.

divider cat paws oct 2024

How to Safely Introduce Your Cats

1. Quarantine Your New Cat and Introduce Their Scents First

The first way you should introduce your older cat to your new kitten is to allow them to smell each other while keeping your new kitten separated, such as in a spare room where they have access to their own food, water, litter box, and bed. You can rub a towel or blanket on your pets and then put the pieces of fabric in the other’s vicinity so that they start to get used to the other’s scent. Next, put them in the other cat’s “territory” to explore without the other cat being there. You can also rotate the cats between the two rooms. Avoid letting them see each other immediately. This should be a slow process that takes at least a few weeks.

young couple reading good news in email on laptop
Image Credit: fizkes, Shutterstock

2. Slowly Increase Access

After the cats seem comfortable with the smell of each other, then you can slowly start increasing their access to each other. First, let them see each other without any contact, and let them interact through the door. Then a face-to-face interaction can be done by putting one in a crate and allowing them to be in the same room under your supervision. Split them up if any aggression starts to show, as this can make the situation stressful for both cats.

Make sure the earliest visual introductions don’t allow the cats to physically access each other. Over time, you’ll be able to allow them to get close to each other with only a screen or gate between them. Increase their exposure to one another until you feel comfortable putting them in the same room as each other, but always with your supervision. Over time, they should get used to each other and will hopefully become good friends.

If there is any aggression, go back a step. Don’t get impatient with this process. Introducing your older cat to your new kitten and helping them learn to like each other can take a while!


3. Monitor for Issues

Once your cats are fully introduced to each other, there may still be tension between the two of them. This is a difficult adjustment for your older cat that requires a lot of patience. Cats hate change, after all. Monitor them closely and try to allow them together only with supervision for several weeks. If your cats are left to their own devices, then aggression and stress may occur without you even realizing it’s happening.


4. Provide Safe Spaces

Your older cat is used to the entire home being their territory, but now they have been put into a situation where they must share the space. Ensure that both of your cats have safe spaces they can go to when they need a break from each other. This may be on a shelf, in a closet or bedroom, or somewhere that only one of the cats can reach. If your older cat isn’t allowed a way to escape from the kitten when they’re overwhelmed or stressed, then they are likely to resort to aggression or withdrawal.

blue-eyed-white-fluffy-himalayan-cat-in-hepper-nest-bed
Image Credit: Hepper.com

5. Keep Their Belongings Separate

Along with having their own safe spaces to retreat to, cats should have their areas to eat, sleep, and toilet. For litter boxes, the rule is to have one per cat, plus one extra.


6. Praise Their Progress

Whenever you notice that your cats are behaving appropriately toward one another, be sure to reward the good behavior with praise and treats. This encourages your cat to continue the good behavior and creates a positive association with the other cat!

divider cats oct 2024

In Conclusion

Slow, controlled introductions are the key to helping your older cat adjust to the presence of the new kitten. Kittens can be little energy bombs that are a lot to take in, especially for an older cat that isn’t used to the energy. Be patient as you allow them to learn about each other.

In some cases, pheromone plug-ins or calming supplements may be needed to help during the adjustment period. If one or both cats seem to be experiencing extreme stress or aggression, then you need to contact a vet for help. Some behavioral issues can be managed with prescription medications, and some may need the assistance of a specialized trainer or behaviorist.

If you need to speak with a vet but can't get to one, head over to PangoVet. It's an online service where you can talk to a vet online and get the advice you need for your pet — all at an affordable price!

PangoVet_Mention-in-Content for PangoVet2 save money

Related Reads:


Featured Image Credit: KristiBlokhin, Shutterstock

Want content like this delivered to you?

Sign Up For Our Newsletter

News, insights, expert advice, and everything cat

* By submitting, you agree to our Terms & Conditions and Privacy & Cookies Policy.

How useful was this post?

Click on a star to rate (you can leave written feedback after clicking submit)

Help us improve Catster for pet parents!

Your feedback really matters.

What did you like about this post? Also how can we improve it?

Join the conversation

Leave a Reply

You’re very welcome to leave a comment or question. Please know that all comments must meet our community guidelines, and your email address will NOT be published. Let’s have a positive and constructive conversation.

Talk With A Vet Online

Peace of mind,
anywhere, anytime

Affordable vet advice

How to Stop a Cat From Bringing Dead Mice Home: 5 Vet-Approved Methods

If you’re the owner of a cat that ventures outdoors, you’ve probably come across a few interesting offerings left for you when they...

What Age Do Cats Stop Playing? Vet-Reviewed Tips on How to Keep Yours Young at Heart

From running after shoelaces to chasing and pouncing on teasers, most cats can’t resist fun activities that trigger their natural hunting instincts. Cats...

Walk Your Pet Month 2026: How & When Is It Celebrated?

Many people do not walk their felines. However, they are missing out on a fun and easy way to exercise their cat and...

How to Keep Cats Away From Bird Feeders: 6 Proven Methods

Bird feeders can add color and life to your yard or garden, but they can be a death trap if you have skilled...

More related

International Cat Rescue Day 2026: How & When Is It Celebrated?

International Cat Rescue Day has been celebrated around the globe since 2019 on March 2 of each year. It is a day to...

Catster Photo Contest: Cats of the Week Winners (November 21, 2024)

This Week’s Winner Silliest Cutest Most Dignified Most Expressive Best Action Shot Sleepiest Enter Your Cat Submit your kitty for a chance to...

Siamese Kittens for Sale: 2026 Breeders List in Canada (BC, Ontario, Quebec, Alberta)

Catster advocates for adopting before shopping, though we fully understand there are many reasons for seeking a breeder. So, we encourage it to...

Only Natural Pet EasyRaw Freeze Dried Treats Review 2026: Pros, Cons, & Verdict

Three weeks ago, I introduced you to Only Natural Pet, a Colorado-based online retailer of natural pet products. While I’ve been a customer...

Keep reading

What’s the Price of Spaying or Neutering a Cat in Canada? 2026 Costs

If you don’t want to breed cats, it’s essential to consider a spaying or neutering procedure. While felines aren’t as expensive to own as canines, the costs still adds up. It’s also something you can do to reduce your pet’s...

neutering cat on a vet's operating table

Alternatives to Declawing Your Cat: 8 Humane Options

On paper, declawing your cat might seem like a simple way to stop your furniture from being ripped to shreds, but the reality is that it’s a cruel and painful operation that can lead to long-term pain, discomfort, and behavioral...

cat claw

How to Teach a Cat to Fetch: 8 Vet-Reviewed Steps

Fetch isn’t just for dogs—some cats love it too! While teaching a cat to fetch might take some work, once your cat gets the hang of the game, it can be a great way to have fun together and give...

cat fetching a ball

How Long Do Maine Coon Cats Live? Vet-Verified Lifespan & FAQ

Considered the largest of domestic cat breeds, the Maine Coon holds a special place in the hearts of feline lovers worldwide. They tend to be laid back, intelligent, and friendly, and they share their warmth and joy with friends and...

male blue tabby maine coon cat

4 Best Oral Flea Treatments for Cats in 2026 – Reviews & Top Picks

Like dogs, cats need regular flea medication to keep the pernicious little bloodsuckers off your cat’s silky fur. Fleas can transmit several dangerous pathogens to your kitty, from bacterial infections to tapeworms, as well as serious conditions, such as anemia...

young woman giving cat a tablet pill

Does Baby Powder Kill Fleas on Cats? Vet-Reviewed Facts & Safety Explored

Fleas are cats’ most common skin parasite. They not only cause skin problems but can also transmit diseases to you and your cat. Finding effective and safe ways of killing fleas is essential to avoid problems. Baby powder contains talcum...

Baby talcum powder container on wooden background

How to Remove a Tick From a Cat: Vet-Approved Steps & Advice

Removing a tick from a cat is not difficult, but it may not be as easy as you think. The hardest part is keeping your cat still, but the process is quite simple with a tick removal tool. You must...

removed tick from cat

Do Cats Recognize Their Owners? Vet-Verified Facts & FAQ

We won’t waste any time. Yes, cats recognize their owners—and any cat owner can attest to this. When you get home from work, you are quite sure that the enamored beast meowing, rubbing, and bunting your whole body wouldn’t act...

Cat Yoga Home Owner