An old neighbor abandoned his male cat. I had the cat fixed a couple of weeks ago. I have an only child male fixed cat for three years. These two cats have seen each other through the window for months when the old neighbor was still around. He had a police report on him and had left him for days without food or water so I started feeding him. I would approximate his age at around 10 months and mine is 3. My indoor cat would always bat at him through the window. I decided to fix him and keep him inside to heal but now he doesn't want to leave. He gets along great with my dog and uses the litter box. The problem is that he and my resident cat do not get along. The stray will try and challenge him then my cat will start growling and hissing but the other cat doesn't back down. I seperate them before there is a fight. Plus I have tried using a water bottle on the stray to deter the bullying I am not really sure which one has the problem or its just the both of them I have been doing all the steps, two litter boxes a piece, separate food dishes and keeping them separated and have tried feliway. Its not like they haven't been seeing each other for months. But as soon as I let the stray cat out of my room he will go up into my cats domain causing problems so then I seperate them again. I do know the outside cat gets along with others as I have seen him, but he was stalked by another orange cat outside. The temps here have dropped substantially as I had a spot for him outside. As soon as I ever opened the door though he would bolt in. I am wondering if I should just try and find the outside cat a new home or if there is a chance they will ever get along. I guess I am asking if this is a lost cause or has anyone ever had any luck with this.