I agree with play felt .... The diapers of today specifically pampers are 12-hour diapers and my own children would sleep all night between 11-12 hours and not be changed. Only time they ever leaked was when I needed to go up a size. I change my dcks twice at 11 (right before lunch) and after nap. If they poop in between those times then of course I change it right away. Most of the time there is barely anything in it and I have never had a dck with diaper even remotely close to doing damage to a child's back.