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Will Sibling Cats Mate? Vet-Reviewed Ethical Issues & Prevention Tips

Written by: Christian Adams

Last Updated on February 18, 2024 by Catster Editorial Team

Two orange kittens standing in hay

Will Sibling Cats Mate? Vet-Reviewed Ethical Issues & Prevention Tips


Dr. Luqman Javed Photo


Dr. Luqman Javed

DVM (Veterinarian)

The information is current and up-to-date in accordance with the latest veterinarian research.

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Cats are one of the most popular pets around the world. With their cute and cuddly personalities, it’s no wonder why people love having cats as part of their families. But when two cats from the same litter live together, will they mate? Yes, cats from the same litter can indiscriminately mate with each other when there is an opportunity. However, there are a few things you can do to prevent this from happening.

In this article, we’ll look at whether sibling cats can mate with each other and if it’s a good idea.

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Will Cats Mate If They Are Related?

When cats are from the same litter, they are considered siblings and may have a close bond. However, unlike humans, cats don’t mate for pleasure. Cats only mate for reproduction, and feline siblings can and do indiscriminately mate with each other if a female comes into heat and a sexually mature male sibling is nearby.

This is definitely undesirable, as you may soon find yourself with more kittens that you can handle. Furthermore, breeding between related cats can produce kittens with genetic defects or traits that may be passed down.

Just as sibling cats can mate with each other, a mother cat can mate with one of her male kittens. Likewise, a female kitten’s biological father can mate with her if she comes into heat. All of these circumstances can lead to an increased risk of genetic risks being passed down to kittens.

persian kittens lying on bench
Image Credit: Jenni Ferreira-Shutterstock

Ethical Issues With Inbreeding Cats

There are conflicting opinions when it comes to breeding cats from the same litter. Some sources say that it is acceptable to inbreed and register the kittens as purebreds, while others say that it’s not a good idea.

Ultimately, you must consider the evidence that shows the risks of inbreeding cats. If you prefer to play it safe, it’s probably best that you don’t allow your sibling cats to mate.

But given that cats don’t share the same morals as humans, you will have to be the one to prevent them from mating if you don’t want any potentially unhealthy kittens.

How to Prevent Sibling Cats From Mating

If you have two cats from the same litter and you want to be vigilant in ensuring they don’t mate, there are a few things you can do.

The most practical option is to spay or neuter both cats. This will prevent unwanted litters, and an early spay or castration (neutering) surgery can offer some health benefits to cats as well 1. Your vet will be able to give the best advice on when to have this procedure done based on your kittens’ age, health, and other factors.

Another somewhat controversial option is to keep the cats separated and provide them with different litter boxes and food dishes in separate parts of the house. This will make sure they don’t come into contact with each other while they are eating or using the bathroom.

However, all it takes is one moment of carelessness during a heat cycle that allows both individuals to come into contact with each other, and therefore, this option isn’t practical. It is also difficult to keep two cats separated all the time in the same house while ensuring they both get adequate attention, playtime, and interaction from you.

It is also worth noting that even if you do separate your cats successfully, you may still have to endure unwanted behaviors from them. A female in heat will yowl excessively, attempt to escape, and may even spray around the house. Likewise, if a male senses a female in heat nearby, he too will try to escape to mate with her and may resort to spraying around the house. A female in heat can also attract stray or feral males near your house, leading to potential cat fights and unwanted noise.

If you notice that your cats are trying to mate, it’s best to separate them immediately. However, this, too, is easier said than done, as cats can do the deed very quickly whenever you’re not looking.

The use of diapers to prevent mating in cats isn’t considered effective in most cases. Cats can also easily wriggle free out of a diaper, and diapers do have their downsides as well, such as increasing your cat’s risk of urinary tract infections and ammonia burns.

savannah kittens playing
Image Credit: Kolomenskaya Kseniya, Shutterstock

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Mating between sibling cats is not recommended, as it can produce kittens with genetic defects. The best course of action is to spay or castrate (neuter) both cats before they reach sexual maturity. Other options are theoretically possible but not always practical and very cumbersome. They also don’t offer your pets any health benefits and still come with annoying behaviors, such as spraying and yowling.

Featured Image Credit: Olgaozik, Pixabay

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