My fiance's brother is his best man. Even though he will know a good 1/3 of the people at our wedding and be busy with best man duties he has asked his mom to ask us to include his best friend, wife and son on our guest list b/c they are his best friends and he wants them there to hang out with. Yes I'm a little stressed b/c our guest list is almost 400 but I'm mainly stressed b/c if his friends are there he might be so busy hanging out with them he might neglect best man duties and I don't want my fiance's feelings to be hurt. I also don't want to cause a rift by not inviting them when I've been asked to do so....I feel like it's a no win situation. Help!