Anne Caroline Salisbury is the maternal great-grandmother of which wife of King George VI and the mother of Queen Elizabeth II and Princess Margaret, Countess of Snowdon?
Queen Elizabeth The Queen Mother Elizabeth Angela Marguerite Bowes-Lyon (4 August 1900 – 30 March 2002) was the wife of King George VI and the mother of Queen Elizabeth II and Princess Margaret, Countess of Snowdon. She was Queen of the United Kingdom and the Dominions from her husband's accession in 1936 until his death in 1952, after which she was known as Queen Elizabeth The Queen Mother, to avoid confusion with her daughter. She was the last Empress of India.
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.