Dr. Kevin Cahill; Hugh Morton; Carole Radziwill

Dr. Kevin Cahill, director of the Tropical Disease Center at Lenox Hill Hospital, shares his book, "To Bear Witness: A Journey of Healing and Solidarity." Conservationist, photographer, and mountain owner Hugh Morton shares some of his photographs and explains how he came to own Grandfather Mountain in North Carolina. Carole Radziwill on her book, "What Remains: A Memoir of Fate, Friendship and Love," which chronicles her experiences of breaking news with Peter Jennings and Diane Sawyer and dealing with her husband's battle with cancer.