In April 2004, Barbara Egbert and Gary Chambers and their precocious 10-year-old daughter Mary embarked on a 2,650-mile hike from Mexico to Canada along the famed Pacific Crest Trail. This the well-told tale of their epic adventure, which required love, perseverance, and the careful rationing of toilet paper. Six months later, Mary would become the youngest person ever to successfully walk the entire trail.The trio weathered the heat of the Mojave,...