Having recently had some dietary restrictions placed upon me, I got to wondering about what you would do if you were travelling and you or your child had severe allergic or anaphylactic reactions to food or environmental stimuli. I have a friend who has a child with life-threatening food allergies. I asked her how they do holidays.
She said that they generally go to her parents' place (out of town) or other relatives. They did consider a trip to New Zealand (only a few hours on a plane), but she quickly realised that they couldn't even do that. She pointed out that many airlines still serve peanuts, and there would be a very high chance of there being peanut residue in the seat upholstery. Let alone not knowing what ingredients are present in the airline food - even if they brought their own, because those around would still be consuming it, and that's not even thinking about the food or other allergens available in different holiday destinations.
I had never considered this before. I now have great sympathy for the difficulties that people dealing with such allergies have to overcome in order to do a simple thing like going on holidays. If you have succeeded in holidaying with an anaphylactic, please let us know how to do it!