When to transition from Crib to "big bed"
http://www.parenting.com/toddler/development/tran…. "Before you announce that it's time to switch, look for clues that your child is ready to leave the crib. If he or she is already jumping (or falling or hanging) out of the crib, then it's time. This usually occurs when a child is 1-1/2 to 2-1/2 years old, but there's no specific age or height requirement. If your baby is content to sit or stand in the crib with the mattress at the lowest setting without trying to get out, you may have more time. Once your child is able to hike his leg up to the edge of the top railing, which is usually around 35 inches, or if the child's mid-chest is even with the top railing while standing, it's time to move on from the crib. The decision to transition should be more about safety than the child's desire to move to a big kid bed."