Actually if your son can eat fish, it's not too bad wor, salmon, tuna and white fish etc...chicken? It really depends on what he's allergic to. My little son is allergic to dairy (moderate) and peanuts (mild) from skin prick test. But I suspect he's also allergic to potatoes and corn. The safest thing to eat is rice but my doctor told me if we dont expose them a little to the food that they are allergic to, they will take a longer time to outgrow it. He suggests giving him broth/soup of food, which has small amount of well-cooked protein in there to desentitize him. My elder son used to have moderate beef allergy so i gave him beef soup once a week. Now he's not allergic to beef anymore. Of course you cant do that with the food he has severe allergy to. If you are interested you get your doctor's opinion on this as this maybe different with your kid.