On May 1, 2015, while vacationing in Mexico, the husband of Sheryl Sandberg, the chief operating officer of Facebook, died suddenly; Dave Goldberg was just 47. Then known for her bestselling 2013 book "Lean In," which urged women in the workplace to stand up for themselves, Sandberg unexpectedly found herself confronting her toughest challenge, as a single mother of two young children. In an emotional and wide-ranging interview, Sandberg talks with "CBS This Morning" co-anchor Norah O'Donnell about how she and her children worked together to move forward after the loss. She also talks about coping with grief and other life lessons she explores in her new book, "Option B: Facing Adversity, Building Resilience and Finding Joy," co-written with friend and psychologist Adam Grant.