My older cat suddenly hates my kitten, help!

[maymayandricky]

my mom recently found a 2 day old kitten on the side of the road, cord still attached and all, and we took every precaution to introduce them slowly when he was old enough, now he's about 4 months old and all of a sudden about three weeks ago my oldest cannot stand him. she is five years old and we had her ever since she was a kitten as well, not as young as him though. anyway, at first she would be very civil with him, like she would let him walk up to her and just sit and watch him. but now they cant even be in the same room together without her hissing and growling, and they eat separately and we tried to put my cats litterbox (the oldest) in my room but she wouldnt use it. my mom thinks the changed happened whenever we put their litterboxes in the same room together and its really unfortunate that we lost all of the progress we had with making them friends. now shes starting to take her hatred for the kitten on us, she attacked my mom a few hours ago in her face, luckly she isnt hurt but now we are really scared of what she's going to start doing, i just really need advice on how to get her back to how she used to be.

 

[Furballsmom]

Hello,
Your cat is likely reacting to another, strange, animal in her vicinity and due to that stress is upset with everyone who is near her.

Use calming products, and don't approach her, let her approach you on her terms and be very calm then, and keep the kitten away from her until this gets resolved.

You might also consider getting them both in for a wellness check if they haven't had one recently, sometimes an underlying illness can cause a cat to behave in unusual ways.

 

[FeebysOwner]

Is this kitten neutered? If not, hormones might be coming into play. And the older cat attacking a human is a reaction to the 'hype' she is feeling from the kitten - called re-directed aggression.

Separate them, and start over with introductions, but only after he is neutered if he is not already. That means separating the litter boxes again too and putting hers back to where she was used to having it.
Re-directed Aggression In Cats – TheCatSite Articles
How To Successfully Introduce Cats: The Ultimate Guide – TheCatSite Articles

 

[maymayandricky]

yes he isnt neutered we were planning on it but we've been really busy, but we'll definitely make it more of a priority now, thank you so much for the resources too, we did separate the litterboxes again so hopefully after he's neutered we can start introducing them again