S.B.
My son stopped sleeping in his crib at 17 months old- he had started going to daycare where they took naps on mats and he never wanted to go back in his crib! We did do a toddler bed for a couple of years before putting him in a twin bed - he had a small room and we thought he needed more play space. We did gate the doors of the room so he couldn't get out by himself during the night and that was mostly for my peace of mind!