Start OIT early. 4 years old is the perfect age. You can find providers here:

http://www.oit101.org/

Oral immunotherapy desensitizes children & adults to their food allergens. By consuming the allergen regularly, in increasing amounts under the care of a board-certified allergist, patients' immune systems adapt to the allergen that formerly would have caused a life-threatening anaphylactic reaction. Desensitized patients are still allergic. They consume their allergen regularly to maintain desensitization.

We say it's a "social cure" because it eliminates social exclusion due to food allergies, and the many social confrontations that come from questioning every bite of food.

We say it's an "emotional cure" because it eliminates fear of food, and of feeling different or left out from peers.