Book excerpt: Since the beginning of the twentieth century, millions of anxious parents have turned to child-rearing manuals for reassurance. Instead, however, they have often found yet more cause for worry. In this rich social history, Ann Hulbert analyzes one hundred years of shifting trends in advice and discovers an ongoing battle between two main approaches: a “child-centered” focus on warmly encouraging development versus a sterner “parent-centered” emphasis on instilling discipline. She examines how pediatrics, psychology, and neuroscience have fueled the debates but failed to offer definitive answers. And she delves into the highly relevant and often turbulent personal lives of the popular advice-givers, from L. Emmett Holt and Arnold Gesell to Bruno Bettelheim and Benjamin Spock to the prominent (and ever conflicting) experts of today.