Christie was educated home, where her mother encouraged her to write from very early age. At sixteen she was sent to school in Paris where she studied singing and piano. Christie was an accomplished pianist but her stage fright and shyness prevented her from pursuing a career in music. When Christie's mother took her to Cairo for a winter, she wrote there a novel. Encouraged by Eden Philpotts, neighbor and friend in Torquay, she devoted herself into writing and had short stories published.
Every murderer is probably somebody's old friend.
It was to be useful when she started writing mysteries. He tapped his forehead. These little gray cells. It is 'up to them' - as you say over here. Miss Marple, an elderly spinster, was a typical English character, but when Poirot used logic and rational methods, Marple relied on her feminine sensitivity and empathy to solve crimes.