Book excerpt: It's one of the most shocking unsolved missing-child cases in the world. Where is Kyron Horman? Why hasn't the woman who police suspect is responsible for his disappearance-Kyron's stepmother-been charged? On the last day he was seen, June 4, 2010, the boy with the toothy smile, crew cut, and glasses posed in front of his science project on frogs. Kyron grinned for a photo taken by his stepmother. She said he walked to his second-grade classroom and turned to wave at her. Then he vanished. That Kyron disappeared from his grade school got the attention of parents around the world. The twists of the case -adultery, sexting, murder-for-hire-keep the story in the spotlight. On the tenth anniversary of Kyron's disappearance, New York Times bestselling author Rebecca Morris tells for the first time the story of the investigation and the toll the boy's disappearance took on his family and law enforcement. Based on years of research and interviews with people close to the case, including Kyron's mother, Desiree Young. the book is the story of the boy's disappearance, the suspicion that quickly fell on one member of a messy blended family, and how Desiree Young turned grief into advocacy. "Boy Missing" examines what recourse families have as they wait for a loved one to be found. It challenges a common assumption in no-body cases: that prosecutors must wait until there is a confession or remains are found. No-body cases can be prosecuted successfully. Jeff Guinn, author of "Manson" and "The Road to Jonestown: Jim Jones and Peoples Temple," calls "Boy Missing " "an important book and one readers will never forget." Rebecca Morris is the author of "If I Can't Have You: Susan Powell, Her Mysterious Disappearance, and the Murder of Her Children," "Ted and Ann: They Mystery of a Missing Child and Her Neighbor Ted Bundy," and other books. A veteran journalist, she appears frequently on network and cable TV as a crime expert.