Falling from Grace — Jane Godwin

It was all meant to be just a game, but now Grace is missing and may not even be alive. During an elaborate game of hide-and-seek on the beach, twelve-year-old sisters Annie and Grace are caught in the rising tide, and Grace seems to have been swept away. In the midst of this, fourteen-year-old Kip is also in the wrong place at the wrong time. Finding Grace's abandoned back-pack sets off a chain of events that lands Kip under police surveillance. As the search for Grace intensifies, suspicions grow. But can Kip piece everything together and clear his name before it's too late for Grace? Told in Kip's and Annie's alternating voices, this spellbinding mystery looks at the choices young people make-and their consequences.