February 5, 1908 - January 4(?), 1969: Age 60
The Hilton sisters were conjoined twins: technically what that means is that they were identical twins whose bodies were joined in utero. Daisy and Violet were fused at the pelvis and lower spine and share blood circulation, but did not share any organs.
They were born to a single barmaid named Kate Skinner. The birth must have been extremely difficult, as they were joined at the buttocks (think about it -- ouch!), and according to their biographer Kate believed their condition was God's punishment on her for adultery. She was so horrified by them that she willingly gave them to her employer, Mary Hilton, who saw commercial potential in the girls.
Their childhood was interesting, to say the least, but not pleasant. Hilton strictly controlled the girls using threats and physical abuse. There were taught to sing and dance and were on display from birth. At the age of three they began touring: first England, where they were born, and then Germany, Australia, and finally the USA. Hilton had a daughter, Edith, and acquired a husband in Australia. When she died in the 1920s she "willed" the girls to her husband and daughter.
In 1931 Daisy and Violet sued their "managers", winning only $100,000 (a fraction of what they had earned for the family) and, more important, gaining their independence. They left the sideshow world, became American citizens, and moved to vaudeville. Daisy dyed her hair blond and they began to wear different outfits. They also smoked, drank, had affairs, and starred in two Hollywood films, Freaks and Chained for Life.
When Violet became engaged, they travelled all over the US to try to find a clerk who would grant them a marriage license: they were denied on the grounds that, because Daisy was not also engaged, it would be immoral. Eventually Daisy found a husband as well and both twins married. Neither marriage lasted.
In the 1950s they opened a snack bar in Miami, but it didn't survive. They continued to make public appearances and it was during one of these in 1962 that their agent abandoned them with absolutely no money in Charlotte, North Carolina. A grocery store manager hired them to work as clerks, and they settled in to life in Charlotte very comfortably, working in the store until their death, and renting a house across from the church they attended.
In the winter of 1968 Violet caught the Hong Kong flu, a virulent strain that infected an estimated half million people that season. Just as she got better, Daisy caught it. They were off work, but their boss called every day to check on them. One day they didn't answer, and he and his wife went over to their house to check on them. Police were called to pry the door open and the twins, now 60, were found dead inside. They were lying on a heating grate on the hall floor.
You can see Violet and Daisy performing here, on YouTube.
You can see a clip from a documentary about present-day conjoined twins, Abby and Brittany Hensel, here. Abby and Brittany are 16, and dicephalic, meaning they have two heads, share many major organs, and each have one leg and one arm. The girls are quite sweet and the life they lead, thanks to a sensible and supportive family and community, quite normal.
Sources: Wikipedia, Sideshow World, Daisy and Violet Hilton