The Forgotten by Faye Kellerman

Rina Lazarus and her husband, LAPD Homicide Lt. Peter Decker, are shocked by an outrage that cuts close to the spiritual heart of their family. Rina's small storefront synagogue has been desecrated with anti-Semitic graffiti and grisly Nazi death camp photographs. The alleged perpetrator is seventeen year-old Ernesto Golding, a "rich kid" obsessed with haunting suspicions about the origins of his Polish paternal grandfather. Then Ernesto is found brutally murdered, along with his therapist, Dr. Mervin Baldwin, at an exclusive nature camp that caters to moneyed, troubled children. For Decker and his wife, unraveling the truth behind Ernesto's violent death becomes more terrifying with each sinister twist. For lethal secrets with roots in the horrors of a past generation are coming to the surface, propelling Peter and Rina into a ghastly world of ruthless parents and damaged youth—and toward a dark evil and its ultimate retribution.