My younger daughter was thought to be lactose intolerant when she was born so i was given lactose free milk formula but it still contained all the calcium she needed. After she was 1, I started to re-introduce cows milk and she is now absolutely fine with it and has no intolerance to it. Sometimes it is just that they have an immature digestive system that they grow out....
Soya milk is not good for babies - especially girls as it has too many hormones in it. Rice Milk is popular in the States but not so much here in the UK and I cannot bear the smell!
Hope that helps!