Has she been diagnosed with a true dairy allergy or can she just not handle it? Hayden was tested for a dairy allergy but it was never positive but he could not handle any dairy, I couldn't drink it when nursing, he couldn't eat it, he def reacted to it even though it showed he wasn't allergic. So since he wasn't actually allergic they knew he wouldn't have a reaction where he would stop breathing so they did tell us to test him every 3mo or so because kids tend to outgrow them. They said most outgrow by age 2, usually around 12-18mo though, but if he hadn't by age 3 most likely it would stick around and at that age they would also retest for the allergy. He ended up outgrowing it at about 16mo, but still can only tolerate small amounts, mostly cooked. If she's just intolerant and not truly allergic I would test her and see how she does, just start with very small amounts. Our dr told us to start with butter because it's broken down the most, then yogurt, the cheese then actual milk.