QUESTION: My younger female cat has started hissing and picking fights with my older male cat for no reason. She runs around the house swatting and hissing at him at unexpected times. I don't know why she has started doing this. She even hissed at me one time now...and she is usually such a momma'a girl
sounds to me like something has frightened her and she is blaming you and your other cat for her fear. this is not unusual and is known as trauma aggression.
Aggression is often a sign of fear for a cat and when something unexpected frightens them they become fearful and seem to place this fear with someone or something else. As I say this is common, sometimes after another cat has visited the vets this can happen.
What needs to happen is for your cats confidence to be restored in both you and the other cat. this is done with a slow process of reintroduction in a confined space. this process is described here
I know it can seem a bit of a slow process but it is the only way that your cat can find her confidence again and loose the fear as it were.
best wishes and I hope all is back to normal soon
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QUESTION: Thank you for the response...I just want to give a little more detail...just so I feel better....she is not fixed...I'm not sure if that matters...but the older cat (male)is. She doesn't always pick fights but has so more increasing and just for the last couple of week...but at the same time she will let him bathe her and she will sit with him for a short while. I think the reason she hissed at me is because I did scare her at that moment...but she has been extremely affectionate with me. I just want to make sure that this information isn't something I should have left out. She has seemed to be a lot more "scard" with noises though.
thank you for the additional information but it doesn't really change my response. However cats which are not neutered can be more aggressive generally as they are more territorial and likely to feel threatened more. So you may want to consider having her spayed as this will make her a less frustrated and generally more contented cat.
bet wishes Kate