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Why are my sister cats suddenly fighting and attacking each other?

Updated On September 23rd, 2025

Pet's info: Cat | Norwegian Forest Cat | Female | spayed | 4 years and 8 months old

Why have my cats (who are sisters) suddenly turned on each other and viscously started attacking the other one?

1 Answer

Most Helpful Answer

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Answered By Angel Alvarado, LVT

Licensed Veterinary Technician

Published on March 2nd, 2016

It may be due to illness or injury. It can also be redirected (or displaced) aggression. This is when one cat is unable to directly respond to a perceived threat and "vents" on whoever is closest. This is usually an owner or another pet. Never handle or grab your cat if she is displaying aggressive tendencies. This can lead to a serious bite or scratch. Schedule an exam with your vet to rule out medical causes. If they are indoor cats, provide a ' cool down' period by separating them. Keep stray or strange cats away from windows or doors and out of your yard. Control what your cat sees by closing doors or drawing the blinds. Consider using pheromone products to decrease anxiety/stress level in the house. Search www.pet360.com for pheromone products.

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