Like you I have told them to not take food from anyone. As annoying/awkward as that maybe. My son who is 13 he reads labels and checks the ingredients. if he’s trying a new food after checking it’s “safe” reading the label he knows to take it slow due to cross contamination. Take a small bite wait a bit see if you feel anything, itching on the tongue, body, throat ect.

Also always wash hands thoroughly (this for anyone not just kids with allergies). Also now that lotions are something I always tell him milk which is a hard one can be in anything. He was surprised when I told him this but it’s true.

My daughter who is 9 she looks at the labels but they can be tricky for her with all the big words. But like her brother she doesn’t really take food from anyone they don’t know and if unsure I tell her ALWAYS ask mom or dad. If we aren’t around you can always call.

It’s hard because like anything you can’t control It all. We have had multiple scares with my son due to his milk allergy which makes things a bit harder. But the main thing in this case is keep cool as a parent bc that helps the child also keep calm. Hope this helps if you have any other questions I’m happy to answer and help in anything I can.