The title "Whistle Down the Wind" originally comes from falconry and means "to let a falcon fly away free."
Mary Hayley Bell wrote the original novel as a vehicle for her daughter Hayley Mills, who plays Cathy.
Shot largely on-location in the bleak countryside around Burnley in Lancashire.
In the novel, the children's mother is absent because she abandoned her husband for another man and ran away with him to Africa. In the movie, she is absent because she died.