Robert Gascoyne-Cecil, 3rd Marquess of Salisbury prime minister of his lifetime. Attlee immediately replied: "Salisbury". The 6th Marquess of Salisbury commissioned Andrew Roberts to write Salisbury's authorised biography, which was published in 1999. After the Bering Sea Arbitration, Canadian Prime Minister Sir John Sparrow David Thompson said of Lord Salisbury's acceptance of the Arbitration Treaty that it was "one of the worst acts of what I regard as a very stupid and worthless life". The British phrase 'Bob's your uncle' is thought to have derived from Robert Cecil's appointment of his nephew, Arthur Balfour, as Chief Secretary for Ireland. Fort Salisbury (now Harare) was named in
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