I was allergic to milk and would get painful stomach aches and cramping by eating tiny amounts of dairy product. The good news: kiddo may grow out of it. I think it was mostly sorted by middle school for me. Early grade school years were much worse. All margerines are equal for me, but maybe the technology is better today. I cannot say if I was allergic to part of milk (lactose vs fat) or not. As a kid I managed this fairly well myself. I asked about milk in everything and did not eat anything containing dairy. Also try butter buds which my mom liked in old age when she could not eat butter.