Conjoined twins happen when a single fertilized egg slits after 8 days leaving twins attached to each other.

This report is based on "Body Doubles: Siamese Twins in Fact and Fiction," an exhibit constructed by Laura E. Beardsley at the Mütter Museum, Philadelphia, PA, Spring 1995.

Conjoined twins in early european history

Throughout history, conjoined twins have appeared in myths and legends. The Greek and Roman god Janus had two faces, one young, one old. Centaurs, a combination of horse and man, may have been inspired by parapagus twins who often have four legs. A common heraldic symbol, the Double-Headed Eagle, is common throughout Central Europe.

One of the earliest documented cases of conjoined twins are Mary and Eliza Chulkhurst, also known as the Biddenden Maids. Born in 1100, the sisters lived for 34 years in Biddenden, County of Kent, England. Mary and Eliza, though often depicted as joined at the hip and shoulders, were likely pygopagus twins who were joined at the buttocks and lower backs. After the death of one sister, doctors hoped to save the life of the other by separating them surgically. The surviving twin refused, declaring, "As we came together, we will go together." She died several hours later. Upon their deaths, a local church received 20 acres of land. In remembrance of their generosity, small cakes and biscuits imprinted with the image of the sisters were given to the poor every Easter Sunday. Nearly 900 years after their deaths, the Biddenden Maids are still honored by this unique service.

In the sixteenth century, the French surgeon Ambroise Pare, believing that conjoined twins were "contrary to the common decree and order of nature" struggled to determine the cause of conjoined twins. Although many of his explanations were superstitious (God's anger, the Devil's influence, God's desire to show power, and the influence of what a pregnant woman saw were all listed as possible explanations). Pare also attributed conjoined twins to several types of constriction, including too tight a womb, tight clothes, and the manner in which a woman sat while pregnant. These early theories were reflected in those of scientists twocenturies later who suggested that conjoined twins resulted from the blending of two initially independent twin embryos or from the fertilization of one egg by two sperm.

Chang and Eng, the well publicized "Siamese Twins," were born in Siam in 1811. They were joined at the lower chest by a narrow band of flesh through which their livers were connected. Chang and Eng spent their first seventeen years devoted to their mother and to the business they began to support their family. In 1829, the adventurous brothers accepted the "invitation" of Captain Abel Coffin to travel to America. A small amount of money was given to their mother, and permission to travel was gained from the King of Siam. Upon their arrival in Boston, Chang and Eng began a long career as a public exhibition. Captain Coffin served as their manager, and the brothers were billed as "The Siamese Double Boys."

After several months in America, Chang and Eng left for England. While there, they were exhibited in the most famous venues and met members of the royal family. Chang and Eng were also the subjects of numerous medical examinations to determine the true nature of their connection and the feasibility of surgical separation, which was deemed impossible. During the daily shows, the brothers performed acrobatics and feats of strength, and displayed their connecting band. After enjoying tremendous success in England, Chang and Eng were denied entrance into France because officials there believed that pregnant women who saw the unusual brothers would bear similarly deformed babies. Eventually, Chang and Eng returned to America.

In 1832, at the age of 21, Chang and Eng ended their contract with Abel Coffin. When they were 28, Chang and Eng retired to a small town in North Carolina. Their first business venture, a country store, was unsuccessful, so they bought land and became farmers. During the early 1840s, they became naturalized citizens of the United States, adopted the last name Bunker, and began a search for "a couple of nice wives." In April, 1843, the search was ended when Chang married Adelaide Yates, and Eng married Sarah Anne, her sister. Over the next thirty-one years the brothers fathered a total of twenty-one children.

During the 1850s, and again after the Civil War, Chang and Eng returned to public exhibitions. In 1860, they met the famed showman, P. T. Barnum and worked for a brief time at his museum in New York City to support their growing families. Barnum also sponsored their tour to Europe. While in Europe, the brothers once again investigated the possibility of separation. The danger was still deemed too great, and surgery was refused. As their health declined, the brothers desired to return home, and they came back to North Carolina in the early 1870s.

On January 17, 1874, Eng was awakened in the middle of the night by a strange sensation. Looking towards his brother, Eng quickly realized that Chang had died. Eng called for his son William, who ran through the house shouting "Uncle Chang is dead!" Within hours, Eng was dead, too. Several weeks later, the bodies were brought to Philadelphia by a commission appointed by the College of Physicians of Philadelphia. An autopsy was performed by Drs. Harrison Allen and William H. Pancoast at the Mütter Museum. It was determined that Chang had died of a cerebral clot. It was unclear, however, why Eng had died. Some physicians suggested that he died of fright. Today, it is thought that Eng bled to death, as the blood pooled in his dead brother's body.

Chang and Eng changed the way society viewed conjoined twins and people with profound physical differences. They proved that those who were different can have normal lives: jobs, spouses, and a healthy family. Chang and Eng introduced the term "Siamese Twins" into our language, and introduced the world to a side of nature that was usually hidden away, ignored, or feared. Chang and Eng led the way for numerous other conjoined twins who have since benefited from the acceptance they demanded and received from society at large. For further information on Chang and Eng Bunker, see Wallace and Wallace, 1978.

The "siamese twins" as cultural metaphor

By the time they died, Chang and Eng were among the most widely known people in the United States. They were the subjects of newspaper articles, books, poetry, satires, lithographs, and plays. They were also a popular subject for masquerade parties. But at that time, these United States were not so united, and in Chang and Eng, Americans saw their own political struggle embodied. Alison Pingree (1996) has documented the tensions surrounding the "Siamese Twins". As "America struggled with its configurations of government (divided states within a united nation) and domesticity (marriage, in particular)," the twins continually raised the question: Are they two or one? The twin's bond was seen as an argument for union and the fusion of the states, while the alternative explanation was that such a connection was "monstrous" and unnatural. Similarly, while the story of the twins' marriages was seen as the triumph of domesticity, these "marriages raised the specters of homosexuality, incest, adultery, and exotic orgies of flesh which profoundly confronted the heterosexual marital norms of Victorian America."

This tension was not merely implicit. It became explicit in the advertisements for the twins. In 1830, Massachusetts Senator Daniel Webster made a stunning speech against the separatists in Congress. He concluded it by urging loyalty to "the sentiment, dear to every true American heart--Liberty and Union, now and forever, one and inseparable!" This phrase was to become so popular that it even got into McGuffy's Reader to be memorized by schoolchildren. The motto was also reprinted on the 1836 handbill accompanying the twins' performances. The handbill was entitled "A Few Particulars concerning Chang-Eng, The United Siamese Brothers." Under the title was an American Eagle with shield, emblazoned with "E pluribus unum." As a legend, if people didn't understand the point being made, was Webster's quotation: "Union and Liberty, one and inseparable, now and forever." The use of Chang and Eng to model American politics was continued into the 1840s, and the material stressed that they were really one person (as in the hyphenated name Chang-Eng). The attempts to surgically separate them and the ultimate decision not to sever the strand were seen as potent political allegories.

he sexual tension was explicitely commented on also. Before their marriages, speculation was rife as to how such unions could be made. They had "each found his other half," and even though unmarried, could never be single men. Pamphlets written about the twins' marriages showed only one home (when they actually lived in two) and compared their domesticity with that of their homeland. But in pointing out that they were now "superior" to the polygamous customs of Siam, they also invited speculation that a piece of that exotic culture was alive and thriving in North Carolina.

Pingree views Chang and Eng as offering "an open canvas upon which America could encode its dominant ideologies of democracy and domesticity. Ironically, though, even as the 'United Siamese Brothers' were presented as idealized literalizations of brotherhood and sameness, and of romantic and marital stability, their contorted, fused bodies also offered, to such ideals, deep challenges indeed."

Millie-Christine, the two-headed nightingale

Life was much more difficult for two pygopagus girls born into slavery on July 11, 1851. They were also in North Carolina, but Millie and Christine McCoy were separated from their family and sold several times. Some of their owners recognized the commercial value of the unusual sisters and put them on public display. As toddlers, the twins were purchased by their last owner, J. D. Smith, who subsequently reunited the girls with their family. Smith assumed the role as manager to the twins' growing career on stage.

While appearing in New Orleans a year later, Millie-Christine was kidnapped by a man Smith had hired as their exhibitor. As "stolen property," the girls could not be shown publicly, but instead were made available to small, private groups. Several years later, Smith was able to locate the girls in London. After a lengthy court trial, Millie-Christine were returned to their owner and distraught mother, Monimia. Before returning to America, where their career continued to progress, Millie-Christine met Queen Victoria, who thought them charming and unusual.

Billed as the "Two-Headed Lady" or the "Two Headed Nightingale", Millie-Christine enjoyed tremendous success in show business. They danced and sang songs written especially for them. Like Eng and Chang before them, the sisters withstood regular medical examinations to determine their physiology. Doctors were often quoted in the advertisements printed for each of the twin's appearances. As a result of the Civil War, Millie-Christine were freed, but they chose to remain with their manager's widow, earning as much as six hundred dollars each week.

Violet and Daisy Hilton

Because of the severe nature of their connection, the Tocci brothers never learned to walk without assistance. As in the case of some conjoined twins, each boy controlled only one leg, and they never were able to coordinate their movements. They were able to write (one was left-handed, the other right-handed) and each had artistic talents. After twenty difficult years touring, the twins retired to a secluded home near Venice, Italy. They married sisters and lived another forty-three years in seclusion.

Two of the most scandalous and dramatic conjoined twins in modern history were undoubtedly Violet and Daisy Hilton, pygopagus twins born in Brighton, England on February 5, 1908. According to the official biography written as part of their stage act, their mother was unmarried so the babies were quickly and quietly sold to a local midwife. Their guardian, Mrs. Mary Hilton, was a tyrant who held the twins against their will for nearly twenty years. She forced them into a life in show business where they sang, danced, and played the saxophone and violin. After a dramatic escape and court case, Violet and Daisy finally gained their independence.

The Hilton sisters' career, now under their own control, blossomed. They performed in the 1932 film Freaks and several years later starred in Chained for Life, a lurid tale in which one sister stands accused of murder, but questions are raised as to the fairness of sending her to jail if her inncoent sister must go as well. Both sisters eventually married, but neither of their marriages were successful (Daisy's to performer Buddy Sawyer, lasted ten days.) By the 1960s, their careers had ended. Violet and Daisy lived for several years in North Carolina, where they worked in a local grocery store as check-out clerks. In January, 1969, Violet and Daisy died of complication of influenza.

Recent conjoined twins

When Yvonne and Yvette McCarther were born on May 14, 1949, their mother faced a tremendous dilemma. The babies were joined at the head, and were among the rarest of conjoined twins. The girls had separate brains, but shared a circulatory system so they could not be separated. Initially, Mrs. McCarther resisted offers by circus owners to put the girls on display. However, faced with numerous hospital bills, she and her daughters travelled with the circus for two years. When the debts were paid, Mrs. McCarther took the girls home and raised them with her other children. Yvonne and Yvette, like so many conjoined twins before them, quickly learned to live as normal children, running and playing with their siblings. The sisters attended local school and as teenagers embarked on a successful career as gospel singers. At the age of 38, Yvonne and Yvette enrolled as nursing students in Long Beach, California. In January, 1993, at the age of 43 and just a few months short of their graduation, Yvonne and Yvette died at home.

In September, 1974, a dramatic medical procedure took place at Children's Hospital in Philadelphia. Chief Surgeon Dr. C. Everett Koop led a team of twenty-three doctors in the dramatic separation of 13-month-old ischiopagus girls from the Dominican Republic, Clara and Altagracia Rodriguez. Though not life-threatening (they had crossed ureters and shared only a liver and a part of the colon) their close connection meant that they could not walk or sit properly. The five hour surgery was a complete success.

In recent years, no set of conjoined twins has captured our attention quite like Angela and Amy Lakeberg. Born in Indiana on June 29, 1993, the babies were joined at the chest and shared a heart and liver. They could not survive together so it was decided to separate them, ultimately sacrificing one for the other. The surgery took place at Children's Hospital In Philadelphia when the girls were seven weeks old. Angela, the stronger of the two, was chosen to be the survivor. Angela never went home. After ten months in the hospital, she died of pneumonia. Her death raised powerful questions about the ethical and economic costs of separation. For some the financial expense was too much (well over a million dollars). For others, it was worth the pain and suffering. The medical community believes that the skills and knowledge acquired from surgeries like the one that separated Angela and Amy would aid in future attempts. The challenge for many observers lies in the conflict between the desire to help medically fragile conjoined twins like Angela and Amy, and the need to justify the emotional and economic costs of their care.

There are numerous conjoined twins in today's society. Surgical separations occur more frequently and with greater success than before. Conjoined twins remain a topic of scientific speculation, public interest, and an image of two minds in the same body.

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