Lizzie Borden, the American Woman of the 19th century who was most famous for killing her parents with an axe, was also involved in an incestuous relationship with her brother. The long lost diary of Dewey Borden, discovered in a trunk in Bangor, Maine, reveals the details of the incest.
His entries regarding his relatinship with his older sister begin shortly after his 13th birthday. He says that "Lizzie came to my room last night after everyone went to bed. She asked me if I enjoyed playing with it. When I told her I didn't know what she meant, she pulled down the covers, pulled up my nightshirt, and said that she'd make a man out of me."
"I awaited her actions and often begged for more frequent visits, but she'd never discuss it during the day. Our monthly adventure was better than any actions by myself and more pleasureable than any nocturnal emission (wet dream)."
Dewey reveals that Lizzie used to come into his room once a month over the next 40 months (always on the night of the full moon) and masturbate him to climax. "The action seemed to give her great pleasure. She'd refuse, however, when I'd offer her similar stimulation."
This activity ceased, however, when sixteen year old Dewey left to attend West Point Military Academy. The next month, instead of stimulating her brother, Borden instead got her pleasure by murdering her parents.
And now you know the rest of the story!