The Secret Keeper by Kate Morton

From the New York Times and #1 internationally bestselling author of The Distant Hours, The Forgotten Garden, and The House at Riverton, a spellbinding novel of family secrets, murder, and enduring love:
During a picnic at her family’s farm in the English countryside, sixteen-year-old Laurel Nicolson witnesses a shocking crime, a crime that challenges everything she knows about her adored mother, Dorothy. Now, fifty years later, Laurel and her sisters are meeting at the farm to celebrate Dorothy’s ninetieth birthday. Realizing that this is her last chance to discover the truth about that long-ago day, Laurel searches for answers that can only be found in Dorothy’s past. Clue by clue, she traces a secret history of three strangers from vastly different worlds thrown together in war-torn London—Dorothy, Vivien, and Jimmy—whose lives are forever after entwined. A gripping story of deception and passion, The Secret Keeper will keep you enthralled to the last page.  Available as a book group to go bag.