HELP WITH 3 CATS.

Currently my mom is moving and has not found a home for her 2 cats yet so in the meanwhile they are at my grandmas.

They were dropped off on the night of Feb 17th. The first of my mom's cat pepper has been hissing at my grandma and the second cat Cole has been hiding and wont come out from under the couch. When i arrived at my grandma's house on Feb 18th i was able to lure pepper out from under the couch. Cole still won't come out from under the couch and i doubt she's eaten or drank water. When we thought pepper was all fine he had begun fighting with my grandma's old cat Pepper. Pepper keeps hissing at my grandma's cat Cosmo and Cosmo just meows at him. Cosmo keeps trying to come out from my grandma's room but is stopped by Pepper.

Hi @Frick  Welcome to The Cat Site.

I think you're dealing with two problems in one here.

First of all your mom's cats are in a new environment and they are scared. You can make them feel a lot more comfortable by keeping them confined to a safe room for now. Choose a quiet room that isn't being used and set it up with litter boxes, they'll need at least 3 for 2 cats, food and water and as much of their bedding, cat trees or other familiar items from home as you can.

You need to make sure that there is no way they can escape from the room, out of a window or into an air vent, for example. It's also a good idea to block off spaces like under a bed or a couch so they don't stay there out of your reach. You can provide them with safe hiding places by draping a blanket over a chair or by covering a cardboard box with something that smells like home.

The idea is to create a small, secure space that smells familiar to them. Scared cats feel much better in a confined space, which is why they are trying to hide under the couch.

If they are going to be at your grandmother's house for a while you could try plugging a Feliway Diffuser in to help keep them calm.

http://www.feliway.com/us/Feliway/FELIWAY-Diffuser

Second, your grandmother's cat is suddenly faced with 2 intruders in his home. You can't expect cats to be as welcoming as people are, I'm afraid. You need to keep them separate until everyone has calmed down and then slowly introduce them.

This article has some good tips for introducing cats to each other.

 [article="32680"]How To Successfully Introduce Cats The Ultimate Guide​[/article]  

If your mother's cats are going to be at your grandmother's place for a month or less I wouldn't even bother trying to get all three cats used to each other. Proper introductions can take a month or more. It would be much easier and much less stressful on all 3 cats if you kept Pepper and Cole confined to their safe room and let Cosmo have the rest of the house.

Good luck, please keep us updated.