Parents are the bones on which children cut their teeth.

Ustinov’s aphorism uses a vivid, slightly comic image: children “cut their teeth” on their parents as if parents were bones. The point is not cruelty for its own sake but the inevitability of friction in upbringing. Parents become the first hard surface a child meets—limits, rules, disappointments, and examples to push against—through which the child develops strength, judgment, and independence. The metaphor also hints at parental sacrifice: being a parent means being used, tested, and sometimes hurt in the process of a child’s growth. It captures the asymmetry of the relationship: children learn by resisting and consuming what parents provide, while parents endure the abrasion.