Hi, I have a 2 1/2 year old son that is allergic to milk, we just did blood tests and it didn't show any allergy to milk, but if I give him a little bit of regular milk he gets red and itchy around his neck, he can have one brand of macaroni and cheese and other brands he can't, because he'll show a reaction, the same with cookies some he can have others he can't, he can have low fat yogurt one brand only, american cheese. Does anyone know what this is? The Doctor says that his not allergic to milk but he shows a reaction to certain foods that contain milk, I don't understand.