Appearances & Headcanons
Max will just be happy everyone is together to celebrate the big guy! I think he might feel a little protective of Shelby and Sasha and conscious of the fact he's one of the only people there that has become friendly with her before this point so he'll work extra hard to be friendly and include Shelby into the convo. If anyone else is feeling any sort of weirdness it might fly under his radar and, of course, he would get in the ball pit because why wouldn't he?