Parliamentary Private Secretary to the Prime Minister Bonar Law's Parliamentary Private Secretary, J.C.C. Davidson acted in effect as his Chief of Staff. Margaret Thatcher's downfall from the Conservative Party leadership in 1990 is attributed by many to the actions of her Parliamentary Private Secretary, Peter Morrison, in failing accurately to count votes amongst Conservative backbenchers. Some Parliamentary Private Secretaries to the Prime Minister go on to hold higher office; Lord Dunglass served as Parliamentary Private Secretary under Neville Chamberlain and later went on to serve as Prime Minister in his own right. There can be multiple Parliamentary Private Secretaries to the Prime Minister at a given time.
Acting prime minister Minister on 16 separate occasions. The term "acting Prime Minister" is sometimes also applied to someone who is temporarily appointed Prime Minister following a death in office (more commonly called a "caretaker Prime Minister" or an "interim Prime Minister"). Examples include Frank Forde (seven days following John Curtin's death), Earle Page (19 days following Joseph Lyons' death), and John McEwen (22 days following Harold Holt's disappearance). Unlike those who merely acted in the absence of a Prime Minister, Forde, Lyons, Page and McEwen were officially commissioned by the Governor General and took the oath of office; they are considered Prime