I've realized that my baby sleeps way better and longer on her belly. I know this is not recommended!!! I'm curious if I was to get one of those breathable mattresses if it would be ok for her to sleep on her stomach. Is the only reason they say not to have them sleep this way because if they end up face down they can't breath? Or is their other reasons? The breathable mattress is super expensive but if this is the only way she will sleep better then I think it's worth it to spend the money for both the babies and me and my husbands sake!