“Typically, people who are close to conjoined twins come to adjust and see them as different but normal; they seem fairly untroubled by the idea of conjoined twins pursuing sex and romance. But those who are watching from afar cannot abide.
“The best example would probably be the story of Chang and Eng Bunker…. One April day in 1843, Chang married Adelaide Yates, while brother Eng married sister Sallie Yates. Based on the fact that Chang and Adelaide had 10 children, and Eng and Sallie 12, it’s fair to say the brothers had sex.
“At the autopsy of the Bunker twins, one of the anatomists opined that their active sex lives ‘shocked the moral sense of the community’ — even though the truth is that the Bunkers’ neighbors appeared to have just accepted the situation. A little known fact is that the Bunker wives’ father originally objected to his daughters marrying the twins not because they were conjoined, but because they were Asian. (This was, after all, the antebellum American South.)
“Yet in the 19th century, when doctors discussed whether the twins Millie and Christina McCoy could marry, one spoke for many: ‘Physically there are no serious objections … but morally there was a most decided one.’ When, in the 1930s, Violet Hilton sought to get a marriage license while conjoined to her sister Daisy, she was repeatedly refused.”
— From “The Sex Lives of Conjoined Twins” by Alice Dreger in The Atlantic
Yes, the Bunkers, the McCoys and the Hiltons all were either born or died in the Siamese Twin Capital of the World.