Eustace Balfour of James Gascoyne-Cecil, 2nd Marquess of Salisbury. His paternal grandfather James Balfour was a nabob who had made the family's fortune as a contractor supplying the Royal Navy in India and became a Tory Member of Parliament (MP), while his mother's father was a Conservative cabinet minister in the 1850s. Her brother, Robert Gascoyne-Cecil, 3rd Lord Salisbury, was three times Prime Minister before being succeeded in 1902 by Eustace's elder brother Arthur Balfour. Eustace Balfour was educated at Harrow and at Trinity College, Cambridge, where he graduated in 1873. He then studied architecture under Basil Champneys, the designer of Newnham
Records of Prime Ministers of the United Kingdom to at least one other Prime Minister by blood or marriage. Two sets of father and son have successively held the office: The only brothers to hold the office were Henry Pelham, who was succeeded on his death in 1754 by the Duke of Newcastle. Pitt the Younger and Lord Grenville (who directly succeeded the latter in office) were the only set of full cousins to hold the office, their fathers being brothers-in-law. There have been three blood uncle-nephew sets of Prime Ministers: Lord Wilmington was two-greats uncle of Spencer Perceval, whose mother, Catherine ( Compton), Baroness Arden, was a