The retreat / Mark Edwards.

A missing child. A desperate mother. And a house full of secrets. Two years ago, Julia lost her family in a tragic accident. Her husband drowned trying to save their daughter, Lily, in the river near their rural home. But the little girl's body was never found--and Julia believes Lily is somehow still alive. Alone and broke, Julia opens her house as a writers' retreat. One of the first guests is Lucas, a horror novelist, who becomes obsessed with finding out what happened to Lily. But within days of his arrival, the peace of the retreat is shattered by a series of eerie events. When Lucas's investigation leads him and Julia into the woods, they discover a dark secret--a secret that someone will do anything to protect. What really happened that day by the river? Why was Lily never found? And who, or what, is haunting the retreat?