In May 1957, in the small town of Hexham in England, 11-year-old Joanna Pollock and her younger sister, six-year-old Jacqueline, were on their way to church with their friend Anthony when they were struck by an erratic driver.
Almost instantly, the two young sisters were killed. Anthony, just nine years old, died while travelling to the hospital.
It was later discovered that the driver, a local woman who was under the influence of a number of drugs, had intentionally hit the three children after being forcibly separated from her own kids. The case later made headlines throughout Britain, with the woman eventually taken to a psychiatric hospital.
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Following the death of Joanna and Jacqueline, the girls' parents, John and Florence Pollock, were devastated.
But when Florence later fell pregnant, John became convinced that the two girls would be reborn into the family as twins.
The couple, who were devout Catholics, often argued over the premise of reincarnation, with Florence strongly rejecting John's beliefs. It was later reported that the couple's entire marriage was even threatened as a result, with Florence almost filing for divorce.
There was also no history of twins in either parent's family, and Florence's doctor had predicted a single birth, meaning the likelihood of twins was low.
Against all odds, however, Florence gave birth to twin girls on October 4, 1958. The twins were named Gillian and Jennifer.
While the twins were identical, the pair had different birthmarks, which is considered highly unusual.
Jennifer had a small birthmark on her left hip, which mimicked a birthmark that Jacqueline had. She also had a birthmark on her forehead, which was similar to a small scar that Jacqueline had in the same spot.