Princess Margaret, Countess of Snowdon, CI, GCVO, GCStJ (Margaret Rose; 21 August 1930 – 9 February 2002) was the younger daughter of King George VI and Queen Elizabeth The Queen Mother and the only sibling of Queen Elizabeth II.

Margaret spent much of her childhood in the company of her elder sister and parents. Her life changed dramatically in 1936, when her paternal uncle, King Edward VIII, abdicated to marry a divorcée, Wallis Simpson. Margaret's father became king, and her elder sister became heir presumptive, with Margaret second in line to the throne. During the Second World War, the two sisters stayed at Windsor Castle, despite suggestions to evacuate them to Canada. During the war years, Margaret was considered too young to perform any official duties and instead continued her education.

After the war, Margaret fell in love with Group Captain Peter Townsend. In 1952, Margaret's father died, her sister became Queen, and Townsend divorced his first wife. Early the following year, he proposed to Margaret. Many in the government believed he would be an unsuitable husband for the Queen's 22-year-old sister, and the Church of England refused to countenance marriage to a divorced man. Margaret eventually abandoned her plans with him and in 1960, she accepted the proposal of the photographer Antony Armstrong-Jones, who was created Earl of Snowdon by the Queen. The couple had two children. They divorced in 1978.

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