Princess Elizabeth and Princess Margaret, watching Monaveen, owned in partnership by Princess Elizabeth and The Queen, run in at Aintree

Princess Elizabeth (left) and Princess Margaret, in Lord Sefton's box, watching Monaveen, owned in partnership by Princess Elizabeth and The Queen, run in the 1950 Grand National at Aintree. Princess Margaret, Countess of Snowdon, CI, GCVO, CD (Margaret Rose; 21 August 1930 - 9 February 2002) was the younger daughter of King George VI and Queen Elizabeth and the only sibling of Queen Elizabeth II. Princess Elizabeth. Elizabeth II (Elizabeth Alexandra Mary; born 21 April 1926) is Queen of the United Kingdom and 15 other Commonwealth realms. She is the elder daughter of King George VI and Queen Elizabeth. Elizabeth Angela Marguerite Bowes-Lyon (4 August 1900 - 30 March 2002) was Queen of the United Kingdom and the Dominions from 11 December 1936 to 6 February 1952 as the wife of King George VI. After her husband died, she was known as Queen Elizabeth The Queen Mother, to avoid confusion with her daughter, Queen Elizabeth II. (Photo by: Universal History Archive/Universal Images Group via Getty Images)