Flesh and blood - Jonathan Kellerman

When Alex Delaware first saw Lauren Teague she was a sullen teenager with the usual bad grades at school; moody and uncommunicative with her parents - which is why they thought she needed to see a psychologist. Years later, Lauren's mother is pleading for help once again. Lauren has vanished -- and she thinks Alex can find her. He reluctantly agrees to try, but as he starts to investigate Lauren's troubled past, he is drawn into the shadowy worlds of fringe psychological experimentation and LA's seedy sex industry. Sensing that Lauren's dark family secrets may hold the key to her disappearance, Alex disregards the advice of his trusted friend, LAPD detective Milo Sturgis, not to get involved. As his quest for the truth beomes an obsession, he is prepared to risk his relationship with long-time lover Robin Castagna, and even his own life...