The kidnapping and murder of Charles Lindbergh's son in 1932 inspired that element in Christie's novel two years later. The novel used many elements of the real life case: a young child, firstborn of the family, was kidnapped for ransom directly from the crib, the parents were famous, the father was a well known pilot and the mother pregnant, and the ransom was paid but the child found dead soon after. An innocent, but perhaps loose-lipped, maid employed by Lindbergh's parents was suspected of involvement in the crime. After being harshly interrogated by police, she committed suicide.