Female cat being violent to brother

[sneakypetesgrandmaisace]

Hi. Really grateful for any advice on this.

I have 2 cats. They are brother and sister from the same litter and they are 6 years old. I've had them since they were kittens.

They are both treated exactly the same and fed the same.

For the last couple of weeks the female cat has been so horrible to her brother. She hisses and growls at him most mornings and evenings. He doesn't do anything to deserve it, he's usually just sitting on the sofa minding his own business and I feel really sorry for him!! He's a sensitive cat and I'm worried that it bothers him. If she continues to do it then I put her outside.

During the day they are cuddled up together on the bed sleeping, so it isn't a consistent thing.

Does anybody have any idea why this is happening and / or what I can do to try to stop it?

Thank you in advance.

Mine are like this and I used to worry about the boy as the girl is horrible to him. But then one day another cat came into our garden and our girl went full on nuts, proper attack mode. It made me realise that in cat language her aggression to our other cat was pretty tame and nothing to worry about.

I've got the opposite problem - my male cat attacks his sister, pretty much every single night when they're both settling down to sleep on my bed
During the day they'll happily sleep next to each other on the same bed or in the conservatory on a much smaller cat bed, but at night he goes for her....
I find little tufts of fur on the floor every single day....

She’s probably just reminding him she’s the boss, it’s fairly typical behaviour for females. As long as it’s all noise and a few light slaps, it’s normal. If you are getting blood drawn, then I would be concerned.

Oh and apparently punishing her for this is not a great thing to do. When I stopped interfering in the power plays it calmed down loads.

Yes Jasper is right. Adult domesticated cats are not naturally friendly (with each other or siblings). If they're both neutered it should be better but still they they are unpredictable.

Our female has always been a "Queen" in her\our house and gets neurotic if she has unfamiliar cats on her patch. They need a special covered bed to go to , to help them calm down (she ran away and hid in our garden once when a stray cat was coming in). also we give her a calming supplement.

If this is a new thing, then I'd keep a close eye on her. Could be she's feeling under the weather and less tolerant, so therefore warning him off.

Thank you for the replies. There has always been the occasional bit of moaning from one of them aimed at the other, but girl cat has definitely taken it up a notch in the last couple of weeks. It's very sad to see as boy cat is very timid. I will keep an eye on her in case there's any other signs of illness