Mortal Memory by Thomas H. Cook

The Edgar Award-winning author "builds a family portrait in which violence seems both impossible and inevitable . . . surprising and devastating" (Chicago Tribune).
Steve Farris was nine years old in 1959, the youngest child in a family that was about to be snuffed out. Around four o'clock on an ordinary November afternoon, Steve's father loaded his shotgun. With calm precision he killed his teenaged son and daughter, and then turned the weapon on his wife. For two hours he waited for his youngest son to come home from school. When Steve did not appear, his father drove away, disappearing for good. Now a successful architect, Farris has spent his life avoiding the memories of that dark day. But questions from an author writing a book about the crime bring back impressions from the days leading up to the killing. For the first time he must confront his awful past, and the terrifying possibility that his father had a reason for what he did.