So you people wanted my references. According to the Pediatric Nutrition Handbook 4th edition 1998 by the AAP Committee on Nutrtion , 85 % of cow's milk allergic children outgrow their reactivity by their third birthday. It goes on the talk of hypoallergenic feeding until the first birthday then a rechallenge in a controlled setting. Studies sited are those of Bock SA and Sampson HA -Rob