Aggressive after other cat gives birth

[wiwao]

Hi, I have two cats, Cordelia, and Ley. Cordelia was adopted from a shelter when she was about 9 months old, and Ley was found abandoned at 4 weeks old. Delia is now 2 years old and Ley is about 10 months. Delia and Ley used to groom, play, and sleep with each other every day, and as far as I know, they considered each other family. Ley recently gave birth to 4 beautiful baby kittens, all of which have homes once they're old enough to leave their mother. I noticed that right after the last baby was delivered, Delia suddenly turned aggressive towards not only the kittens, but Ley. I've tried googling over and over but only get results with a male cat and female cat with the male being aggressive towards the babies, or the mother cat being aggressive towards the kittens. I am very confused as to why Delia would suddenly hiss and growl at Ley when just the night before they were grooming each other. It's understandable for her to be aggressive towards the kittens, but I just can't seem to figure out why she suddenly doesn't want anything to do with Ley anymore. Any and all help/advice is greatly appreciated. What do you think could be the cause of this sudden aggression?

 

[mani]

Hi @Wiwao and welcome to TCS!

Your question hasn't attracted any answers in the behaviour forum so we've moved it here.. maybe our Pregnant Cats and Kitten Care members can help.

 

[Sarthur2]

wiwao

You need to separate the cats for now. Ley and her kittens need the privacy and safety of a room to themselves, and Ley needs her food, water, and litter in that room just for her.

Cordelia perceives the new kittens as a threat to her territory as alpha cat, and she is attempting to let them know this!

She feels displaced, so try to give her extra attention and treats for now, in an effort to reassure her that she is special. Keep her away from the kittens though. Is Cordelia spayed?

Do you plan to spay Ley after this litter?

 

[wiwao]

@sarthur2

Yes, Cordelia came from a shelter so she is spayed. I do plan on spaying Ley as soon as the kittens are completely weaned off of her milk.

Thank you for the advice, Cordelia has mostly just left the kittens and Ley alone, unless Ley happens to walk near her, then Delia hisses at her. I'll start giving Delia more attention and I'll start buying treats as you suggested.

 

[Primula]

You've received some good advice here. I would add that maybe Cordelia is a little bit jealous that Ley has beautiful kittens & she doesn't. Cats feel jealousy too!