Sounds Of Silence by Elizabeth White

Border Patrol agent Eli Carmichael knew the deaf child he'd found outside a Mexican orphanage was harboring a dark secret -- she was carrying a bloodstained knife and was clearly traumatized. To keep her safe, he turned to trusted neighbor Isabel Valenzuela.

A sense of duty had kept Eli close to his fellow agent's widow and her young son over the past year, and now Eli was spending more time with Isabel and the kids, trying to determine exactly what the girl had seen. Under Isabel's gentle care, the child began to open up. But the killers were close by, and determined to silence the girl forever....

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