they also can climb on the crib bumper and fall out so when you notice them stepping on the bumper fix it ASAP. first child was super good at climbing out second one climbed then fell. just watch for any sign of breakage I'm the bone.
it happens. I think that's why they have such tiny brains and more bone around the brain while they are little. I haven't noticed any developmental problems in either child although I don't wish to describe the fall.