Why are my cats attacking my third cat after I returned from vacation?

Because Colby disappeared for a bit, he probably went on an adventure and came back smelling differently. Jack views him as a stranger, and that's why he's acting aggressively. I would separate the cats, and slowly reintroduce them to each other. Take Jack, and put him in his own room with his 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 Colby in Jack's room while Jack 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 Colby 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 Jack out of his room, and see how he interacts with Colby. 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 Jack in his room when you go out until they are comfortable with each other.

This happens quite a bit actually. Could be territorial aggression - she left and now he is trying to tell her the house is his OR it could be that he feels threatened due to the way she smells when she returns. I suggest you start using some Feliway products. I would spray the carrier when you take the cats to the vet and use the diffusers (multicat) in the house. ( https://www.feliway.com/us ) ( https://www.feliway.com/us/Why-Use-Feliway/how-to-stop-cats-fighting )

I hate to hear that. This situation can very very stressful and it's hard to know why this is happening. It's possible Kyo is sick and his odor has changed. It may be worthwhile to have him examined by the veterinarian to make sure everything is ok. It's also possible the cats are seeing or smelling another cats outside and this is causing stress and bullying behavior. Wipe down doorways and windows to eliminate odors. Here are a couple articles to help with cat aggression and stress: https://www.petcoach.co/article/5-tips-to-handle-an-aggressive-cat/ https://www.petcoach.co/article/causes-of-stress-in-cats/ You can help relieve stress by setting aside 30 minutes a day for vigorous play for each aggressive cat, provide climbing opportunities with cat shelves and cats treats, use a pheromone diffuser and provide separate litterbox and feeding stations. Lastly, your veterinarian can provide medications or a special diet called Calm which may help the cats. Best of luck and please feel free to post any additional questions.

Oh dear, how stressful! Unfortunately it can be common for cats to lash out when one cat in the household suddenly smells or acts different - as they tend to do when they come home from the vet. Most of the time they go back to their normal interactions once the strange smell (in this case, from the vet clinic) wears off and the cat relaxes and acts like herself....but in your case, there's nowhere for Tribble to hide and isolate herself while she readjusts to being home. The most important thing right now is to not allow them to fight or have negative interactions. As long as they can be kept separate while they both settle down, they will probably do ok - but if they continue hissing and growing, and worse yet if it escalates into a fight, that could permanently damage their relationship. I would absolutely keep them separate until they seem to be relaxing. I understand that'll be challenging in a 1 BR living space - but if possible, you could put 1 in the bathroom with her own litterbox & food, and then have them switch places tomorrow so they can get reacquainted with each other's smells. If that's not possible, you may need to crate them both while you work on their reintroduction. Perhaps you could borrow dog kennels so they can each have their own living space while they're confined. I know this isn't an easy answer - but the most important immediate intervention is to do what you need to do, to keep them from fighting while the stress levels come down! Finally, adding a pheromone diffuser such as Feliway Multicat may help promote a calming atmosphere. I hope this helps!

Thank you for submitting your question regarding your cats. I suspect that Stella is stressed by the return of her housemate. Callie likely smells and acts a bit different after being gone for so long. I would keep them separate to allow them time to readjust to each other. They should get along fine, but it will take some time. I hope this information helps!

Keep them separated for the time being. Oliver may need a few days to reacclimnate to Minnie. If she allows, a bath may remove any residual outdoor scents that could be upsetting Oliver. Pheromone products such as Feliway spray may decrease his anxiety/aggression as well.

Unfortunately, it is very common for one cat to come home from the vet's office only to have the other cats show aggression toward them. It is not from the UTI itself but likely because of the smells he has on him that are foreign to the other cats. Typically this will stop after a couple days. You could get some Feliway Multicat diffusers to help the situation: https://www.petco.com/shop/en/petcostore/product/feliway-30-day-multicat-diffuser-plug-in-starter-kit