Older cat bullying new cat

[Maxim Pavlov]

Hello everyone.
There are 3 cats in the house. About a year-half a year ago my mother took a new cat. It's a female. The oldest cat is very aggressive towards it, and the new cat is very afraid. If my mother lets her loose in the house, she will be so afraid of the oldest cat that she will stay in a hidden corner where the fat older cat can't reach her for a few days. He's very aggressive and violent towards her. She's usually locked in my parents' bedroom. If the older cat manager to get in he attacks her straight away and he always tries to get in.
Any advice?
Thank you

 

[rubysmama]

Hello and welcome to TCS. Sorry though for the situation that brought you here.

A year and a half is quite a long time, so not sure if there's any chance of makes things better now or not. But it can't hurt to try.

How does the older cat act around the 3rd cat? Are they friends, or is the older cat aggressive towards it too.

You didn't mention, but are all the cats neutered/spayed?

Even though it's been 18 months, since the "new" cat is in your parent's bedroom most of the time, they could try doing a "re-introduction" between her and the older cat.

Here's a TCS article with info on How To Fix An Unsuccessful Cat Introduction | TheCatSite that your parents might find helpful.
Also info on introductions in How To Successfully Introduce Cats: The Ultimate Guide – TheCatSite Articles

 

[Maxim Pavlov]

The 2 older cats are neutered. The new one isn't.
Also it's not a year and a half. It's around half a year to a year.
The older cat the the middle cat get along well. They're playful and also chill with each other most times.
Thank you for the help, will read the link.

 

[rubysmama]

Oh, sorry, misread the length of time. Six months is much better than 18.
And the fact the older cat and middle cat get along, is good too.

I'd suggest that your parents get the new female spayed as soon as possible. Not just because her having endless heat cycles must be annoying everyone. But the heat cycles, along with her hormones, could be having an affect on the older male, despite him being neutered.

Until getting her spayed, I'd keep her away from the older cat. Then when she's back home, and healed from the spay surgery, restart the introductions, as if they'd never met before.

There's still no guarantee they'll ever be friends, but I think there's a chance, and it's certainly worth trying in order to have peace in your parent's home.