Spare the rod and spoil the child. Don't throw the baby out with the bathwater. Life isn't all beer and skittles. A growing youth has a wolf in his belly. To be the black sheep of the family.
Blood is thicker than water.
A chip off the old block. You can lead a horse to water, but you can't make it drink. Death is the great leveller. To pull the wool over someone's eyes. To keep something under one's hat.