Feline Sibling Rivalry?

Question
I recently moved in with my boyfriend and have brought my 2 3y/o neutered male sibling cats with me, Toby and Tiger. My bf already has an 8y/o neutered male named Larry. We are keeping them on separate floors for the time being until Toby and Tiger adjust to the new place and smells. However, my two guys are hissing and growling at each other and cannot stand to be near each other. Tiger is always hiding. This is very strange because they have always been the best of friends ever since I got them at 3 weeks old.

They have only had one face-to-face with Larry and they hissed at him so I separated them because Larry has been declawed and I didn't want him to get hurt. Not a fair fight since both of my guys have theirs. So I have been camping out upstairs with T&T to keep them company in this foreign environment. I have cuddled with them each separately and even had them each purring at one point. When I was petting Tiger however, Toby came over and they started growling at each other again and quickly put an end to our cuddle time. Whenever their eyes meet, the growling, hissing and avoidance starts again.

Now, this is only day 1 of them being here, so I'm sure things will get better but I wanted to get some information from someone who may know a bit more about this. I know that they are probably mad because there is another cat around that they can't get to and are most likely taking it out on each other, which I read can happen.

My question is, should I be allowing all 3 cats full roam of the house or is separating them the best solution at this point? Again, it is only day 1, but I don't want a permanent personality change from Toby and Tiger because they are normally exceptionally friendly and have always been really loving. I hate to see my normally very social cat Tiger hiding in any nook he can find.

I really appreciate you taking the time to answer my question and hope to hear from you soon. Thank you.

~Shawn (Ontario, Canada)

Answer
Dear Shawn,

Your cats may have to wait to determine whether separation is completely neccessary. They may just be fighting because the smell of the new apartment, because cats use sense of smell to see if they recognize eachother.

If they continue this behavior, you must separate them. You can try to stop the behavior by using a simple water gun and telling them no, so they realize what they done was wrong. If they get into a fight, and they do not like eachother anymore, you cannot stop it.

If you just recently got your cats neutuered, it could take some time to ware off, which causes them to behave oddly, and act kind of bizarre.

And yes, if your cats fight way too often, is can permanently change your cats personality forever, due the cause of what happened. Give them a while before you do anything to them, and understand that Tiger may be scared of his new home. If he constantly has his claws sticking out, and his tail is moving back and forth, and some fur sticks up, then he is scared of either his home, or Toby.

Try to introduce Larry to Tiger and Toby, one at a time, and if it doesn't work out, keep them out of site, but hold them, don't let them loose. Cats also get mad because they might want to get into heat, if they just got neutured or spayed.

I hope my advice helped you a lot! And if you need anything more, you can contact me by my e-mail adress again, because I once had three cats at one point, and have an idea that can help you a lot, which is what I did that solved everything. I have a cat named Tobey, right now. Solong, and good luck.

                      -Jenna