I have 4 stray kittens (I say stray b/c even though we live in the country, they have all been very friendly - except for one, who is now friendly after 3 months - since the beginning) that have grown up with my chickens. They showed up with their mother when they were 3 weeks old, and they are now almost 4 months old. They have learned to leave the chickens alone and have been no problem, even to my younger 10 week old chicks. The chickens have no problem keeping them in line. lol
I feed my cats at night after the chickens get locked up, and haven't had a problem with predators, so far.
If it starts to eat your chicken feed, you can always put pepper flakes or cayenne pepper powder mixed in the feed, and that should stop it. It doesn't hurt the chickens, and the other animals don't like it. My cats just have to smell it, and they turn the other way.