Sheryl Sandberg has talked of her grief and feelings about resilience, as she launched her new book, Option B, which has just been published.

The chief operating officer of Facebook, whose husband, Dave Goldberg, died suddenly in 2015, has spent the last few days giving interviews and talking openly about how she tried to help her children to grieve - and learnt to cope herself - after her husband's death.

"Flying home to tell my 7-year-old daughter and 10-year-old son that their father had died was the worst experience of my life," Sandberg wrote in Monday's New York Times. She went onto explain how her friend, psychologist Adam Grant, helped her to discover how children can "persevere through adversity."

"Resilience is a muscle we can help kids build," Sandberg - who has also been interacting with others who have suffered bereavment via her own Facebook page - added. The anniversary of her husband's death is on May 1.