hi my son is 13 months today, on dec 16 i switched him to cows milk and the first week he did fine then he got so constipated and in jan i had gave him a bottle of milk and he threw up all night. i stopped the milk and have been giving him apple juice and prune juice a week later his constipation is gone so do i start him on lactose? My brothers and I are lactose intolerant and so is our mom! while he was on the cows milk i made sure he had a lot of fiber thro out the day and when the constipation started i did try prune juice but it did not work till i stopped the milk. And when he was constipated he was in so much pain, what do i do for him? this is so hard to watch:( hes so unhappy!!!