Calming Collar

[xcourtney3]

My mother in law just moved into a new place that has a resident cat and she has 2 cats of her own. So we've got 1 mean cat, 1 curious cat, and then the resident cat who is being standoff-ish (but also curious). I have one calming collar, which cat would benefit from it the most? (I'm going to discuss more permanent solutions but since they aren't my cats there isn't a lot I can do)

 

[Columbine]

It's almost impossible to answer that without more detail about how each of the cats is behaving. As a general rule, I would use calming remedies on whichever cat seems most stressed and anxious.
Is Your Cat Stressed Out?
It's important to test the cat's reaction to the collar first though. A small minority of cats actively hate calming collars. If the chosen cat is in this group, the collar would makes things worse, not better. Either see how they react to the smell before it goes one, or watch them closely for the first hour or so, and remove the collar if necessary.

Rather than a calming collar, is trying Feliway plug-in diffusers a possibility? I know it's more expensive, but it would help all three cats with whatever issues they're going through.

These articles may help too:-
How To Successfully Introduce Cats: The Ultimate Guide
How To Help A New Cat Adjust To Your Home
Maybe pass them on to your mother in law to help her help all three kitties have a smooth transition.

 

[xcourtney3]

Well I have only seen two of them interacting on video chat. The resident cat was sitting in a crate (not closed in), the other was sitting outside the crate watching and meowing. Later the 2 new cats were in one room and the resident cat came down the hallway and was peeking through the door and watching the new cats. I have yet to see the third cat interacting with the resident cat but I hear he's more aggressive.

I will ask about Feliway.

 

[Columbine]

It' so hard when you can't see and feel the vibes in person, especially with introductions. I'm so sorry I can't be more help

 

[xcourtney3]

It's fine! The 2 new cats were previously indoor/outdoor cats and only one of them went outside. (The one that's curious about the resident cat) So I'm assuming he has seen a lot more cats and is therefore not as stressed about being around a new cat.

We once had to stay at my mother in law's old house in an emergency situation, and we had to bring our cats. We kept them isolated in one room (it was only for a few days) and the more aggressive cat also showed aggression towards my cats by hissing at the door. The other was not interested