Dark of Night. Blood of the Fae, #2.7

Long tormented by the murder of his family, Lord Blackburn has spent years seeking answers about the uncanny nature of their deaths. Despite the claims of the authorities and lack of clear evidence, he holds Other responsible for their brutal end-and he's resolved no others will suffer such a fate. With that purpose foremost, he buries his grief in his mission for legal reform. Yet he meets obstacles at every turn, and his endeavors to change the laws of Byren appear as doomed to failure as his quest to find the truth.
Hope wears thin until a mysterious message arrives, promising answers about the past. To uncover the truth, he'll take any risk necessary, even return to the edgetown where his wife and son were killed. To survive what awaits him there-and gain justice for his loved ones-he'll have to enlist unlikely allies and face what lurks in the dark of night. This novelette takes place concurrently with Ruins of Bone, book two in the Blood of the Fae series.
While a self-contained story, it assumes prior knowledge of the Blood of the Fae world.