Angel, my suggestion would to try to narrow down the problem. If you know she gets gas with dairy, the problem could be due to the milk sugar - lactose - or the milk protein - casein. If it's the milk sugar, you could just go lactose free. But if it's the protein, you'll have to go dairy-free completely - no dairy of any kind.
Try going to Enterolab.com and read about the fecal antibody test for casein intolerance. You may want to do that test to find out. If it comes back positive - no dairy at all. If it's negative, restrict lactose.
I have tried acidophilus capsules and have had amazing results. They cannot be harmful because they are the healthy bacteria that our bowels need to help break down and absorb nutrients. Check out ACIDOPHILUS. Google it. I have not found there to be any risks but have told others about my experience with it and have even been attending college classesand while flus and colds and pneumonias have been going around, by taking mega-doses, I have been healtheir than ever before! Quite large amounts can be taken without any danger. (i take the 2-billion live culture capsule; as many as 20/day when feeling cold symptoms) When I have known that a UTI or yeast infection was coming on- i will also take large doses. For your daughters symptoms, I'm not a doctor and won't try to tell you how much to start with, start low (1-2) and bump up till you feel a correct dose has been found. I wish you the best. I told my doctor about my experience withthis in fighting colds and germs and all he said was...in-ter-esting. I wish doctors would see how it works and some antibiotics might be avoided.