What to Do if Your Kitten and Cat Don't Get Along

Grey tabby kitten with adult grey cat
 Getty Images/Aurimas Skirmantas/EyeEm

Domesticated house cats may be a lot different than their wild relatives, but they still have some similar characteristics, including how they coexist with other cats. Some cats take to new kittens right away, while others need a lot of time to get used to one or may never adjust to a new cat in the house. But why do some cats like living with other cats and how can you help your cat like a new kitten if they don't?

Wild and Feral Cat Behavior

Wild felines, such as bobcats, lynx, and servals, are very closely related to the domesticated cats that we care for in our homes. These wild cats are rarely seen though, especially during the day, because they are naturally secretive and nocturnal. They hide in dens during the day and come out at night to hunt for food alone.

Like wild cats, feral cats also hunt and sleep alone, but if food is being provided to them by humans, they will often live in large groups that are led by a queen cat. This dominant queen is a sexually mature, intact female that will produce litters of kittens. She may be visited by various feral tom cats but these tom cats will not live in this group. The rest of the group is submissive to this queen, otherwise they do not stay in the group long term. As kittens grow up in the group and become sexually mature, they may challenge the queen and leave the group if they are not submissive to her.

This social hierarchy is different than that of the average house cat though because house cats are domesticated, usually spayed and neutered, often not well socialized with other cats, and live in a very isolated environment away from other cats.

Help Your Cat Get Along with a New Kitten

If you have, or even if you haven’t, followed instructions on how to slowly introduce a new kitten to your cat and they aren’t getting along, there are still a few things you can do.

  • Food bowls - Make sure the kitten has its own food and water bowls that are not in the same location as your cats' bowls. Feed them in separate areas so that your cat does not become territorial towards its own food and your kitten still gets a chance to eat. If you need to, feed one of the cats in a separate room and close the door.
  • Playtime - Get the feather wand or another interactive toy out and allow both cats to play together.
  • Sleeping areas - Provide separate areas for sleeping for both your cats. Do not try to give your cats’ old beds or condos to the new kitten, as your older cat has already established that those are its items, not the kittens’. Providing your older cat with areas outside the kittens' reach are also good for cats who need to get away from an aggressive or annoying kitten.
  • Litter boxes – Make sure you have one more litter box than you have cats. This means if you have two cats, you should have three litter boxes. There should be no direct line of sight between the boxes in case both your older cat and your new kitten are in different boxes at the same time.
  • Pheromones – Sprays, wipes, and diffusers containing special feline pheromones can be purchased and should be utilized as long as necessary. These pheromones help cats feel relaxed and safe and may benefit both the new kitten and your older cat during the introduction phase.
  • Treats – Pet your new kitten and then allow your older cat to smell you while you are petting them and giving them their favorite treats. This will help teach your cat that the smell of the new kitten is not a bad thing. Over time they may start to associate the smell of the kitten with treats, making it a positive scent. The same can be done for times that the kitten is in the same room as your cat and you see them interacting nicely. 
  • Separation – If you are unable to monitor your cat and kitten and you are worried about one hurting the other, make sure they are safely separated. A bathroom with a litter box, bed, and bowl of water can be where one of the cats stays if you are away at work or at night. This is especially helpful for kittens who won't leave your older cat alone.
  • Keep things calm – Sometimes unusual things that scare a cat will cause them to show displaced aggression on a new kitten. Cats are creatures of habit. so don’t opt to make major household changes, such as renovating the kitchen and ripping up carpet, or have a party where you set off fireworks in the backyard in addition to introducing them to a new kitten.
  • Don’t allow them to fight – While they may want to, do not allow your cat to do anything more than hiss and swat at the kitten.  If you are concerned a fight is about to happen, distract the cats with a loud clap of your hands or use a water squirt bottle.

Sometimes giving your cat time to adjust to a new kitten is what is needed. But if your cat was not well socialized before the age of three, it may be very difficult for them to get along with a new kitten. Some cats are better off being the only cat in a home, while others may not like one kitten and take to another one based on their personalities.