There are only a couple of times when it's absolutely necessary to move a child out of a crib into a regular bed. One is when you know a sibling is on the way and the other is when baby is playing Houdini at night and climbing out. Other than that, I think the best time to move to a big bed is when the child is showing the ability to get into bed and stay in bed without too much trouble. A child that is somewhat trustworthy without supervision in their room is also helpful. Unfortunately, for some folks, baby learns how to climb out of the crib and tries repeatedly to escape when he doesn't want to go to bed. As much as it hurts the grown ups, that is an absolute MUST move to a bigger bed. A child can fall head first, or catch an arm or leg on the way down and really do some damage so if your baby is starting to climb out, it's definitely time! If you are expecting a new baby, you probably want the transition to go smoothly so you'll want to take the crib down and put it away for a while. That way you can make a huge fuss over the new bed and when you do bring the crib out for the new baby it won't be like you're taking the older child's crib away and giving it to the new baby! If you don't have an escape artist, and you aren't expecting a new baby that will need the crib, there is no pressing need to move to a big bed until the child needs more room to stretch out.

Getting the baby to move to the new bed is a matter of insane repetition. If you don't have one already, make a bedtime routine that you can work through every night. Bath, brush teeth, diaper change, jammies, read a book or two and then go to sleep. Usually baby will love all the parts right up to the go to sleep part. For the first several nights they'll get up, over and over again wanting to play or watch TV or sit with you. Eventually, they will fall asleep from exhaustion from walking all over the house. Your job is to calmly remind them that it's bedtime and to lay in bed and go to sleep. You'll have to do that several hundred times. For the first few nights it helps if you can also turn off the TV and the lights in the other parts of the house and keep your activity to a minimum so baby sees that they aren't missing anything fun. In time, how long depends on the child, they'll realize that getting up only gets them turned right around and back to bed and they'll stop getting up. You may want to allow them to read quietly or play with some soft blocks or quiet toys so long as they stay in their room and just check them periodically and put them to bed if you find them asleep on the floor. If you are worried about stairs or other nighttime dangers, you can put a gate across the door but be sure to responds when baby calls for you. If they think they've been abandoned up there, alone, in the dark, they'll think bedtime is pretty horrible and it will make it impossible to get them to go to bed easily. However, if they trust that you'll come if they need you, they won't resist bedtime so much and they may just play in their room until they peter out.

What kind of bed baby moves to is up to you. Some people prefer transitioning to a toddler bed, some like a twin or full sized bed with bedrails. My personal preference was a twin mattress directly on the floor. A few blankets or pillows on the floor and it was safe even if baby rolled out! When they got good at staying on the mattress we moved it into a bed frame.