Why Is My Kitten Attacking My New Kitten?
If you have noticed that your kitten is attacking your new kitten you may be concerned and looking for reasons why, and what you should do…
Why Is My Kitten Attacking My New Kitten?
This is completely normal behavior when it comes to kittens and even adult cats. Cats are naturally both playful and territorial. When they are kittens, play helps to sharpen their skills and their bond, but it also helps to establish a ‘pecking order’ among all of the felines concerned.
You’ll even see kittens occasionally attacking momma, who will often ‘attack’ back, but without biting hard enough to harm them and only swatting the kittens with her claws retracted.
Play-fighting during this time is an important part of socialization, as it teaches the kittens how to play well with others and also important lessons like how hard they can bite during play and how to hit each other without involving their claws!
Is it normal for a kitten to attack a new kitten?

Two brown tabby kittens on top of chopped wood.
Yes, you should expect kittens to play-fight with each other, but remember as well that they are babies when you hear the occasional upset kitten when the fighting gets rough. Don’t let it worry you – your kittens are learning important lessons – and unless blood is being drawn then you won’t need to interfere by separating them.
How do I know if kittens are fighting or playing?
You can tell if the fight is a play fight by the results. Play fighting should not involve removing patches of fur or bites and scratches that cause bleeding.
The occasional cuts and nicks are okay, as kittens are still learning how to use their claws, but if you notice it as a regular occurrence then you may need to separate and monitor the kittens during play sessions.
What should I do if my kittens are fighting?
If your kittens are fighting, go ahead and let them. While it looks very ‘rough and tumble’ to us, catfights are quite normal in the realm of kitten and even adult cat behaviors. These little skirmishes help to establish which cats are dominant and they also help the kittens to learn how to use their teeth and claws.
As long as fur isn’t being removed and blood isn’t being drawn, let your cats play as they will. It’s completely natural and should lessen over time as your cats slowly grow and mature.
How do I get my cat to stop attacking my new kitten?
Cats are creatures of habit. They have certain spots where they like to spend specific times of the day and they are very annoyed or even stressed when anything in the house changes. They can also be a bit jealous, at times, and notice that you are spending a lot of time with that new kitten.
When they are attacking the kitten, however, it’s not always jealousy. Check to see if the bites are drawing blood, as this is very important. While some cats will greet kittens with open arms, others will be a bit rough on the newcomer as a way of establishing their territory.
This can include biting behaviors that look scary to us but stop short of actually drawing blood. You will even see a kitten’s mother do this from time to time as a way to say ‘pay attention’ or to simply let the kitten know who is in charge.
You can help your older cat to be less uncomfortable by simply moving your kitten’s bowl a bit further away from the main feeding area and by making sure that your cat has somewhere to go that is their own where the kitten can’t go. Don’t worry – your older cat will come around – it just takes a little time!
When do kittens start play-biting?

Two kittens playing on a comforter.
At about 3 weeks of age, your kitten will transform into a ‘bitey little monster’. This is normal for them, as cats learn early to manipulate objects with their mouths. After all, a quick nip makes you react immediately, which is quite amusing from the kitten’s point of view.
This behavior is going to reach its peak at about 9 weeks of age when your little furball will seem like they are biting everything in sight, but be patient with this process. By 16 weeks of age, they will mellow out a bit.
Biting like this is just a part of their development and it teaches useful lessons, such as ‘what do things do when I bite them’ and ‘how hard can I bite while I’m playing’. If your kitten bites hard enough that it hurts, show them by stopping play immediately and saying ‘oww’ while pulling your hand close to your face.
Finally, biting can occasionally be a red flag – kittens with a sore tummy or even a worm infestation may bite out of being in pain, in a sour mood, or to get your attention when they are feeling sick or hurt. If you think that this is the case, an immediate vet visit is the proper next step
How long will it take for my cat to accept a new kitten?
A lot will depend on your cat. With kittens, it tends to be quick and might be as little as 2 weeks before both felines seem to like each other more and start developing a proper friendship. With older cats, the process can take anywhere from 8 to 12 months!
Keep this in mind if your cat is very resistant to befriending your new kitten – especially if, until now, you’ve been living alone with your cat.
Some cats can become a little codependent, especially if they aren’t well-socialized, and in cases like this, your cat may merely ‘tolerate’ the new kitten and continue to do so for many months before the two become friends.
Why are kittens aggressive?
Kittens are naturally aggressive ‘by design’. As cute as they are, these energetic little balls are young predators, and it will help you to understand them quite a bit if you always remember this. During this formative period, kittens are learning how to stalk and subdue prey like they would in the wild.
They are also learning how to socialize with other felines and with the people in their new home. Don’t worry – the worst of it will pass around 16 weeks of age, as your kitten will have learned some foundational lessons by this time and will be less inclined to bite everything that moves quickly in front of them.
Unless of course, it’s a string or a laser pointer, in which case all bets are off!
Why is it important for kittens to get used to each other’s scent?
Scent is important for felines and kittens will quickly learn each other’s scents as well as yours. Have you ever noticed how an adult cat will change their sleeping spots all of the time? This is scent-driven behavior. By keeping ‘on the move’, your cat avoids leaving too much of a scent trace.
This helps to keep them from being eaten in the night by predators in the wild, and it’s a useful enough instinct that domestic kitties still hang on to it. Scent is also the reason that your cat rubs against you.
They have scent glands all over their body – even in their faces – and rubbing you puts their scent on you to mark you as ‘safe’ and trusted.
Why do kittens start biting you?
Your kitten is just playing and learning what’s acceptable behavior with you. You can help to reduce the chances of this by stopping play when your kitty bites, especially if you hold your hand close and say ‘ow’ to indicate that the bite was painful.
When your cat notices this, they won’t stop biting because kittens really can’t help it, but they will learn to bite with less force when they play and will likely bite a little less. By the time they are 16 weeks of age, you’ll even be able to pet them again without immediately getting your hand tackled.
Hang in there – your kitten is just learning how to be a cat, it’s nothing personal!