The good thing about childhood intolerances and allergies is that they are often outgrown. If a person develops an allergy as an adult, they tend to have it for life.
DD1 is allergic to dairy, soy, and eggs, but she is on her way to outgrowing them. Her levels went down drastically between age 1 and 2.
I would avoid dairy completely and take LO to a pedi allergist at age 1 for testing. If it's truly an intolerance, an allergy test will be negative. I would want to have her tested to see if it is actually an allergy. If so, you'd need to be more vigilant in avoiding dairy and have a treatment plan for accidental exposure, [ie, Benadryl, EpiPen].