On 12 January 1976, author Agatha Christie died peacefully, aged 85.

She created the detectives Hercule Poirot and Miss Marple.

By the time of her death, Christie had written more than 80 books. Most of her works were detective novels but she also wrote romances, short stories, poetry and plays.

In 2015, Louise Hidalgo spoke to her grandson, Mathew Prichard.

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(Photo: English detective novelist, Agatha Christie. Credit: Bettman/Getty Images)