Boy! I'm glad I'm not a part of the families on here...I'd.just stay home! Luckily our family actually LOVES my son and WANTS to make the holidays as easy as possible for my son with multiple food allergies.
I am having to try to talk my MIL into making a turkey (the traditional dish in her family) because my son is allergic to both turkey and chicken. She know that our society tend to revolve around food and that my son is already feeling like a freak during the holiday season and, because she loves her grandson, she doesn't want to make him feel worse.
My D has a friend who is very allergic to almost everthing. I would be frightened to have her over for a meal, lest there be an ingredient I forgot about that she'd react to.