I have 2 year old twins that refuse to sleep in their toddler beds. They will fall asleep in them but I find them on the floor in the middle of the night or they are awake all night. In fact we had problems with having them sleeping in there cribs as well. They would only sleep for an hour before being up all night. I am thinking its their mattresses. Just curious what type of mattress would you suggest? I was thinking about getting them those breathable memory foam mattresses. Any suggestions?