As a young student, John Crocker embarked on the adventure of a lifetime, spending eight months in the Gombe forest working with Jane Goodall. He followed families of wild chimpanzees from sunrise to sunset and learned the fundamental behavioral traits of these chimps as they raised their offspring. One chimpanzee captivated him. Her name was Fifi, and she displayed extraordinary patience and reassurance toward her infant, Freud. Upon returning home and becoming a doctor, Crocker found himself incorporating the lessons he learned from Fifi into his work as a father and physician. Crocker shares how his time spent with our closest animal cousins has helped him better understand his patients with ADD, anxiety, and depression, and how primate traits hardwired into our own natural behavior help chimpanzees protect their community, raise their young, and survive. Finally, chronicling his return to Gombe thirty-six years later with his own son, he reflects on how his experience with the chimps has come full circle.