Was Father And Son, Now Worst Enemies!!!

[Susane2763]

I have two male cats one(Socks) about 5 years old, the other(Brutus) is about 2.5 years old. We had Socks, when we brought Brutus and his brother (Roscoe- he has passed) when they were 6 week old kittens. I was concerned because Socks was a unneutered male. I brought Socks into the room where we were keeping the kittens. He went over to them smelled them and took right up with them. He washed them, he would even "protect" them from our dogs!! He took care of them like they were his babies, he would even let them "attempt" to nurse on him!! They have always gotten along, never any hissing or fighting, even as Brutus grew up. This all changed about 3 weeks ago, Socks got outside, ( they are both strictly inside cats) for about 30 minutes if that long. When we brought him inside Brutus started growling and hissing. I thought okay, he smells weird from being outside, so I bathed Socks, thinking that would resolve the issue, it did not. I decided to have them neutered (something I should have already had done), thinking again it would fix things. They both got bathed when we got them back home, because they had urine on themselves from being I their carriers. I was thinking give them a couple of days to recover from the surgeries they will be good again. It did not help, they are still fighting. Sometimes one of them will be curious of the other one, will come up to the other when we have tried to re-introduce them we come up to sniff at the other one, the one being sniffed at will growl and hiss, then it all starts all over again!! Please does someone have any ideas or suggestions? I have tried rubbing one with a towel, taking it to the other one and rubbing it on him. That has not worked either. I want them to get back like them used to be, I hope things will go back to like it used to be!! I don't understand how Socks getting outside for maybe 30 minutes could change their relationship. Please help.

 

[Furballsmom]

Hi - We're glad you're here!
It sounds to me like they need their brains re-wired. If you do a re-introduction you'll need to go all the way back, to completely separating them and VERY slowly bringing them closer to each other, this is going to take time.
Take a look at the info in this article - I'm hoping there's something that helps.
Also, see if some feliway diffusers and other calming products such as treats and even collars help. Good luck!! Let us know what happens.
How To Fix An Unsuccessful Cat Introduction

 

[Mamanyt1953]

Furballsmom is right, they need to be rewired. This is actually so common that there is a name for it, Non-Recognition Aggression. And the sad thing is, that even when they begin smelling "right" again, the damage is done. The GOOD thing is that it is fixable, using the methods in the article that she gave you!

This one will give some additional tips, and help explain what happened:
How To Deal With Non-recognition Aggression In Cats