My ped suggested we 'trial' Grace every 3 months with whole milk yogurt when we were ready. She failed the 15 months (loose runny stools, mucus in stool) but at 18 months she tolerated it ok. It took until 2 years old to pass the cheese test. She is 2.5 and still not drinking milk, but she can handle milk cooked in foods, cheese, yogurt, ice cream in small quantities.
HTH and good luck!