In which year did this British peer and politician whose daughter was Henrietta Ponsonby, Countess of Bessborough pass away?
Henrietta Ponsonby, Countess of Bessborough Henrietta Ponsonby, Countess of Bessborough (16 June 1761 – 11 November 1821), born Lady Henrietta Frances Spencer (generally called Harriet), was the wife of Frederick Ponsonby, 3rd Earl of Bessborough, and mother of the notorious Lady Caroline Lamb. Her father, John Spencer, 1st Earl Spencer, was a great-grandson of John Churchill, 1st Duke of Marlborough. Her sister was Georgiana Cavendish, Duchess of Devonshire.
Robert Spencer, 4th Earl of Sunderland Robert Spencer, 4th Earl of Sunderland (24 October 1701 – 15 September 1729) was a British peer from the Spencer family, the son of the Whig politician, Charles Spencer, 3rd Earl of Sunderland. His mother was Lady Anne Churchill, the daughter of John Churchill, 1st Duke of Marlborough and Sarah Churchill, Duchess of Marlborough. Known as Lord Spencer between 1702 and 1722, he succeeded to the Earldom after his father's death in, but died in 1729 with no children. Therefore, his brother, Charles, became 5th Earl of Sunderland, and subsequently 3rd Duke of Marlborough after the death of his aunt, Henrietta Godolphin ("née" Churchill), 2nd Duchess of Marlborough.