Clarence House has been the official residence of the heir apparent of who?
Charles, Prince of Wales Charles, Prince of Wales (Charles Philip Arthur George; born 14 November 1948) is the eldest child and heir apparent of Queen Elizabeth II. Known alternatively in Cornwall as Duke of Cornwall and in Scotland as Duke of Rothesay, he is the longest-serving heir apparent in British history, having held the position since 1952. He is also the oldest person to be next in line to the throne since Sophia of Hanover (the heir presumptive to Queen Anne), who died in 1714 at the age of 83.
Evelyn Cavendish, Duchess of Devonshire Evelyn Emily Mary Cavendish, Duchess of Devonshire {'1': ", '2': ", '3': ", '4': "} (née Petty-FitzMaurice; 27 August 1870 – 2 April 1960) was the wife of Victor Cavendish, 9th Duke of Devonshire. She was born the elder daughter of the politician Henry Petty-FitzMaurice, 5th Marquess of Lansdowne and grew up amidst public life. Evelyn's marriage to Cavendish, the heir of the 8th Duke of Devonshire, led to her becoming Duchess of Devonshire in 1908. With her position, she oversaw the reorganisation of the Devonshire estates and presided over four English houses and one Irish castle.