Killer in the Canyon - The Lost Gorge Mysteries, #3

The only person who can help Sol find a missing child is the one woman he can't trust. When a strange woman stumbles out of the mountains, disheveled and bleeding, begging for help to find a lost child, Sheriff Sol Chapa stops everything to search. Three days later, with no sign the girl even existed, sympathy turns to suspicion, and the woman disappears as quickly as she appeared. Despite all the evidence to the contrary, Sol is haunted by the small chance that he failed.
Jennifer lies about everything, including her name and her background, but she didn't lie about the kid. She knows firsthand the terrors the backwoods inflict on the young. With no one left to trust, she searches the wilderness herself. Sol can't shake the feeling he quit too soon. Jen won't give up on the missing girl. Neither will survive the search alone.