The first guide in the Little Bodies, Big World series for parents of children aged 0-5. This short, evidence-based guide explains why using correct anatomical names -- penis, vulva, vagina, testicles -- is one of the most powerful things a parent can do to protect their child. Covers what the research actually shows, what the words are and what they mean, how to introduce them at every age from birth to five, and exactly what to say when grandma objects. Warm, practical, and completely undramatic -- because that's exactly how this conversation should feel.