1 / 7The world's oldest set of conjoined twins, Ronnie and Donnie Gaylon, 68, died on July 4, in their hometown of Dayton, Ohio. They broke Guinness Book of World Records as the world's oldest conjoined twins when they turned 63 in 2014.2 / 7Ronnie and Donnie Galyon have been turning heads since they were born on October 28, 1951 to parents Eileen and Wesley Gaylon, who were not expecting twins, much less conjoined twins.3 / 7They were born healthy, weighing 11 pounds, 11.5 ounces, but they spent the first two years of their life in the hospital as doctors struggled to figure out a way to safely separate them. 4 / 7When they were told there was no guarantee that both boys would survive the surgery, Wesley and Eileen refused to operate on their sons.5 / 7For 68 years, the brothers lived face-to-face, fused from the sternum to the groin with one set of lower digestive organs. 6 / 7They were each born with separate hearts and stomachs and had their own set of arms and legs.7 / 7The brothers entered the circus as sideshow performers starting at age three. They were exhibited in an air conditioned trailer and spectators paid to watch them live daily life., they retired from the circus in 1991 and Ronnie said: 'We had fun when we were growing up'