Question: When did John St John, 20Th Baron St John Of Bletso's father die?
Answer: 28 October 1934

Moubray St Andrew Thornton St John, 19th Baron St John of Bletso DL JP (5 November 1877 – 28 October 1934) was an English peer. John Moubray Russell St John, 20th Baron St John of Bletso TD(3 August 1917 – 13 April 1976) was an English peer. The only son of Moubray St John, 19th Baron St John of Bletso and his wife Evelyn, John St John became the 20th Baron Lord St John of Bletso on the death of his father in 1934