Book excerpt: How to react when your toddler bites his playmate or your kindergartner confronts a bully? Drs. Brazelton and Sparrow bring their much-admired insight and support to this crucial, and ever more timely, childrearing challenge. From an early age, babies and toddlers need to assert themselves in a daunting world, yet eventually learn to do this without hurting others. After showing how aggression emerges at each age, Brazelton and Sparrow offer practical, wise advice on anger, fights, self-defense, the fears and nightmares that arise when children become aware of their own and others -- aggression, the effects of TV and video games, and of experiencing real life violence. They offer specific, effective ways to help children understand their own aggressive feelings and channel them into healthy self-assertion in schoolwork, games, and sports.