If you and your child are afraid of the world around you, then stay at home in a bubble.
I would bet this mother complains about EVERYTHING.
It’s not a nut allergy. It’s a Control issue
My wife has a severe allergy to fish and shellfish. She has ended up in the hospital unable to breath along with other bad but less deadly problems. Unfortunately, products that cause her problems are ingredients in many dishes that most people have no idea contain seafood. Things like Worcestershire sauce, certain barbecue sauces, Ceasar salad dressing, many soy sauces and of course anything that has been deep fried with fish or shellfish or grilled next to fish can cause her severe problems.
We would not think of making impositions on others because of her problem. Unfortunately, it is almost impossible to useful information from people who work at restaurants about how their food has been prepared. And it has gotten much worse in our area because of the huge influx of people who do not speak English. The last time she had a severe reaction we had a dish that was served with green vegetables. I noticed that they tasted fishy and immediately cautioned her but it was too late. We had eaten at the same restaurant for years before without having a problem. This time, the employees had reused water that they had been boiling fish in to boil the vegetables.
This was not an accident; we were told that reusing the fishy water made the vegetables taste better, was healthier for people and was helping the environment. Personally, I thought that flavoring the vegetables with fishy water made them taste disgusting. We received no apology and were told that this was how their vegetables were going to be prepared from now on. We of course have not been back and would never consider suing the restaurant.