When he was breastfed he did great. No issues. That being said, I don't have a ton of milk in my diet. In fact, I NEVER drink milk, I only have cheese and yogurt. He still never slept well. When my milk supply dropped (around 9 months) we switched to formula. We were having the sleep issues and just starting with the skin issues. He never had diarrhea from BM or formula. Again this all was right as the cold weather was starting and solid foods were well on their way so it is so hard to tell what was a result from environmental things or food related things. We switched to cows milk at 12 months and he was fine until 15 months drinking two glasses a day. Suddenly at 15 months, the diarrhea started and we ended up going dairy free for 3 weeks and Thad when we figured the diarrhea only came from actually drinking the milk.
So today is our first dairy free day!!