Two Female Cats - All of a Sudden fighting

by Erin Boudreau
(Wolfville, Nova Scotia, Canada )

I have two female indoor cats that been living together for atleast a year. Over the holidays I took them both home to my parents place and let them go outside for a couple hours. They never went far, but ever since one of my female cats are always hissing at people and at the other female cat. I'm back at my place and I notice that they can't even walk by each other without the one female cat "hitting, or hissing" at the other cat. WHY is this happening? Before they use to sleep together, wash each other, play together... any advice?

Answer from Kate
Hi sounds to me like a case of what is known as aggression trauma. It is a strange occurrence but is quite common. I have written a page about this here https://www.our-happy-cat.com/cat-aggression-trauma.html.

best wishes kate

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