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.
Muffie Cabot Mabel "Muffie" Brandon Cabot (née Hobart; born c. 1936) is an American heiress and socialite. During the 1980s she served as social secretary to Nancy Reagan. She is the mother of Ali Wentworth, an actress notable for her appearances on the sketch comedy "In Living Color" and who is the wife of George Stephanopoulos.