My nephew is anaphylactic to nuts and eggs
Certainly changes the simple things in the beginning, birthday cake, always had to take his own, surprisingly at times the children at parties were more aware of cross contamination risk, then some of the adults.
My wife is allergic to something, still don't know what, we have an epipen, and have used it, she came to and said I don't need the epipen, I've said you've had it