<P> On 15 September 2015, coinciding with her 125th birthday, And Then There Were None was named the "World's Favourite Christie" in a vote sponsored by the author's estate . Most of her books and short stories have been adapted for television, radio, video games and comics, and more than thirty feature films have been based on her work . </P> <P> Agatha Mary Clarissa Miller was born on 15 September 1890, into a wealthy upper middle - class family in Torquay, Devon . Her mother Clara was born in Belfast in 1854 to Captain Frederick Boehmer and Mary Ann West as the couple's only daughter . Captain Boehmer was killed in a riding accident while stationed on Jersey in April 1863, leaving his widow Mary Ann to raise her children alone on a meagre income . Mary Ann's sister Margaret had married a wealthy American, Nathaniel Frary Miller, in 1863, and the couple lived in Southbourne, West Sussex . Margaret had no children of her own, and so the two sisters arranged that Clara should be raised by her aunt and uncle . It was here she met her future husband, an American stockbroker named Frederick Alvah Miller, who was the son of Nathaniel's first marriage . </P> <P> A member of the American upper class, Frederick had been sent to Switzerland for his education . He was considered personable and friendly by those who knew him . He soon developed a romantic relationship with Clara, and they were married in April 1878 . Their first child, Margaret Frary Miller (1879--1950), was born in Torquay, where the couple were renting lodgings, while their second, Louis "Monty" Montant (1880--1929), was born in the U.S. state of New York, where Frederick was on a business trip . When Frederick's father Nathaniel died, he left Clara £ 2000 in her own right; she used this money to purchase a villa in Torquay named "Ashfield" in which to raise her family . It was here that her third and final child, Agatha, was born . </P> <P> Christie described her childhood as "very happy". She was surrounded by a series of strong and independent women from an early age . Her time was spent alternating between her home in Devon, her step - grandmother and aunt's house in Ealing, West London, and parts of Southern Europe, where her family would holiday during the winter . </P>

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