Would you have this much stress if they were vegetarian or ate differently than you in some other way? I know a family who's kid only eats chicken nuggets and Mac and cheese and hamburgers. Seriously. He was coddled his whole childhood (like these kids?) and now it's just bizarre (he is 9!).
I went to a parent lecture once and the speaker made a point that resonated with me - important to teach your kids to "eat what's out in front of them". Unless they're allergic. It's just politeness. I took it to heart. My 2 kids will do it now. Not so much in my own home (!) - but at friends and relatives, they will eat at least some of everything. They know they can get something to supplement later if needed, but they have learned that it is polite and respectful to eat what is served. I know some adults who have trouble with that concept. Anyhow - something to consider.

Let your husband worry about these things and deal with the child when there.