Mumof4 - I have also been told to try Bun on dairy every once and a while. The doc wanted us to test it out when he was 9 months old, but it took me until he was a year to actually try. I felt like I had finally got him eating (he didn't start solids until he later due to dairy issues) and gaining weight, so the thought of putting it back in his system was crazy to me. At a year he still had similar reactions when we gave him yoghurt. We tried yoghurt because it is fermented and easier to digest than real cow milk, so if there was a reaction I reasoned that it wouldn't be as bad. I will probably test it out again when he is 18 months. It would be great if he outgrew it though - I would love for him to be able to just eat anything he wanted