A family photograph taken before a Christmas Day massacre holds a telling clue of why the slaughter took place.
In 1929, tobacco farmer Charles Davis Lawson made the unusual decision to take his wife and seven children into town for a studio portrait.
The Germanton, North Carolina, father bought new clothes for his wife, Fannie, and their four daughters and three sons, to wear for the photograph.
It was a highly uncommon thing to do for a working class family, and the secret behind the photo remained hidden for many years afterwards.
Lawson, who had grown up in a sharecropping family, had saved enough money to buy a ramshackle 200-year-old farmhouse close to his brothers' farms.
But on the day of the photo shoot, no one apart from Charlie Lawson knew why he was spending money.
Nor what was to come, his almost complete annihilation of his own family to protect a scandalous secret.
Standing in the photograph at the back are 16-year-old Arthur Lawson, his sister Marie, 17, and their parents.
In contrast with Marie, who is staring directly into the camera, her father, Charlie, is gazing off to the left with a slight smile on his face.
Beside him, his wife Fannie is also looking away and holding the couple's youngest child, 4-month-old Mary Lou.
On a seat in front of them are the younger Lawson children, James, 4, Maybell, 7, Raymond, 2, and Carrie, 12.
On December 25, 1929, 17-year-old Marie rose early to make a Christmas cake, baking two layers in separate pans and icing them ready for the family festivities on the farm, 200km northwest of the state capital, Raleigh.
Some time after this, the middle Lawson girls, Carrie and Maybell, left the house to go and visit their aunt and uncle.
But behind the tobacco barn on the property, their father Charlie was waiting with a shotgun.
The 43-year-old shot his daughters, bludgeoned them to finish them off and placed their bodies inside the barn.
He then returned to the family house where his wife Fannie, 37, was sitting on the porch.
Lawson shot her, and then moved inside where Marie was, and her two younger brothers, James and Raymond, had run to hide.
Charlie shot Marie and then found the two boys and shot them as well.
Finally, he bludgeoned baby Mary Lou, whose cause of death was a fractured skull.
Later, the seven bodies would be found with their arms crossed over their chests and rocks underneath their heads.
Only the oldest son, Arthur, who had been sent by his father on an errand the night before the killing, would survive.
It is believed Arthur arrived back home and raised the alarm, and people began gathering at the Lawson home.
Charlie was missing, but within hours the gathering heard a single gunshot from nearby woods.
Arthur and a police officer found Charlie's body and letters he had written. Footprints encircled a tree it was later supposed Charlie had paced before killing himself.
Charlie Lawson's letters did not explain why he had carried out the bloody massacre.
After the funeral, at which a large crowd gathered around the coffins, the Lawson house attracted hundreds of tourists.
They came and saw Marie's Christmas cake on display, a souvenir of the massacre that was kept under glass after visitors stole some of its raisins.
In 1945, Arthur Lawson was killed in a car crash, leaving a wife and four children.
It wasn't until 1990, that a book about the massacre was published and a cousin of the Lawson children told a 60-year-old secret.
Stella Lawson Boles confessed she had overheard her mother and other Lawson women talking at the funeral about how Fannie had confided in them that she had discovered incest in her family before Christmas.
Fannie Lawson had since agonised about the relationship between her husband, Charlie, and 17-year-old Marie.
It also emerged that weeks before the fateful Christmas, Marie had shared a secret with her friend Ella May Johnson.
On a sleepover, Marie had told Ella May that she was pregnant with her father Charlie's baby and that both her parents knew about the pregnancy.
Another story, from the Lawson family's neighbour, Sam Hill, was that Charlie had forced himself upon his daughter and when she became pregnant, he had warned her that if she told her mother or anyone else "there would be some killing done".
In the family photograph, Marie's belly does not protrude, but she stares stonily from the photograph, while her father looks askance and a little defiant.
The massacre entered folk history in the form of ten songs, two books and a film.