On following instructions
When the in-package literature tells you to put the crib mattress on the lowest setting once your child can pull himself up, for the love of all things sacred, DO IT.
My kid just managed to tumble head first out of his crib, land on the trunk next to the crib, and then fall off of that on to the floor. I caught him just before his head would have hit the hardwood.
He’s a champ, so he’s totally fine, but still - LOWER THE DAMN CRIB MATTRESS.