The first week Squeak visits is fraught with kitty negotiations. While Sentinel is a "live and let live" kitty, Antares spends a lot of time following Squeak around and trapping him in corners. I spend a lot of time saying things like, "Antares! What a cute kitty, let me pick you up!" so he will vacate his stalking and Squeak can go about his business. I think Antares has the cat version of short man syndrome.
After the first week, they've usually got everything all figured out. Then they can all find a spot on the bed and hang out together, albeit separately. Such cute kitties!