Killing Secrets (Thorne's Thorns, #1)
Karen Docter, K.L. Docter

Contractor Patrick Thorne wants nothing to do with another of his parents’ charity cases. He failed his own wife so abysmally she took her own life as well as his unborn son’s. After two years, it’s time to concentrate on the bid he’s won and the saboteur trying to destroy his construction firm.
There is no room for trust in either of their hearts. But trust is all that will untangle the secrets that dominate their lives, free a little girl of her silent prison, and save them all from a serial killer who stands too close.