How do you make cats like each other?

I'm going to guess Milo isn't neutered. Tom cats that aren't, fight alot. Please do get him "fixed, for his sake ,for the sake of his many ,many ,many kittens he's fighting to have that will end up being euthanized because there are no homes for them, and for his future health. Not only will he end up with less injuries but it will also decrease his chances of feline leukemia or F.I.V.from coming into contact with other cats who are infected and will pass it to him thru bites. It will also stop him from spraying because he won't be so territorial. Which leads into your 2nd concern~ how to get the 3 cats to get along. If he's fixed he'll be more mellow and not trying to mate or dominate them . Also if you keep the 2 new cats in a room with food, water and a litter box for 5-7 days they will have time to get to know each other thru smell & sound safely. Then let the3 of them have supervised time together for a short time a couple times a day till they get used to each other. finally they will be fine and you will have peace in your home. By the way, are your friends cats neutered or spayed? If not you are in for constant fights. And that kitten s life is in danger from your Milo. Un-neutered toms are notorious for killing kittens. And while you are getting him fixed, as long as he still goes outside, get his vaccines updated to prevent rabies, distemper, and many other terrible deadly diseases. I'm well aware this all costs$ and most people are short of that these days, so call you local A.S.P.C.A. or shelter, they are usually reasonably priced. Or call every vet near you and get prices. I hope I've been helpful to you, good luck, and please do the responsible thing---neuter your cat!