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My cats fight after one went out. How do I reintroduce them?

Updated On September 23rd, 2025

Pet's info: Cat | Mixed Breed | Female | spayed | 9 years and 2 months old

I have two cats that are sisters, Fergie and Gizzy, both female and spayed. Fergie has become unhappy,hiding and hissing at her sister and us. Nothing else has changed in her. Only thing that happened is while playing with Fergie with a feather toy today, Gizzy ran into the room which startled her and then a hiss fight and small fight erupted between them. She also seems to be a little upset sometimes at Gizzy when she returns from the garden. They're indoor cats.

2 Answers

Most Helpful Answer

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Answered By Dr. Melanie, BVSc MS

Veterinarian

Published on March 25th, 2017

If Gizzy is going out into the garden, then she could come back in smelling differently and that's causing Fergie to be upset. I can give you a method to help them get along again. I would separate the cats, and slowly reintroduce them to each other. Take Fergie, and put her in her own room with her own food, water, and litter box. Keep the door closed, and for a few days, feed them both treats on other side of door so they associate each other's smell with a good experience. Then let Gizzy in Fergie's room while she is in a cat carrier. They can smell each other, but not be in contact. If either becomes upset or show signs of aggression, remove Gizzy from the room, and try again later. Praise them when they interact appropriately. When they are interacting well with each other through the carrier, you can let Fergie out of her room, and see how she interacts with Gizzy. Praise them when they interact appropriately, and separate them with any sign of aggression or upset. I would get a cat tree with lots of shelves to give the cats vertical space to get away from each other. I would keep Fergie in her room when you go out until they are comfortable with each other.

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Related Answers from Veterinarians

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    Answered By Dr. Melanie, BVSc MS

    Veterinarian

    Published on December 10th, 2018

    You'd have to check with your vet first to see if ok to bring all the cats to Patches's appointment. The vet might not like you showing up with all the cats. A short visit may not cause a problem, but if it does, I can give you a method for it. I hope this helps! I would separate the cats, and slowly reintroduce them to each other. Take the cat who is aggressive, and put her in her own room with her own food, water, and litter box. Keep the door closed, and for a few days, feed them both treats on other side of door so they associate each other's smell with a good experience. Then let the other cat in the aggressive cat's room while the aggressive cat is in a cat carrier. They can smell each other, but not be in contact. If either becomes upset or show signs of aggression, remove the second cat from the room, and try again later. Praise them when they interact appropriately. When they are interacting well with each other through the carrier, you can let the aggressive cat out of her room, and see how she interacts with the other cat. Praise them when they interact appropriately, and separate them with any sign of aggression or upset. I would get a cat tree with lots of shelves to give the cats vertical space to get away from each other. I would keep the cat in her room when you go out until they are comfortable with each other.

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