Signed Royal Presentation Photograph of Princess Mary, 1951

The Princess Mary, Princess Royal and Countess of Harewood (Victoria Alexandra Alice Mary Lascelles, née Windsor) (1897–1965) was the third child and only daughter of King George. Princess Mary was born at Sandringham. During the First World War she assisted with projects to give comfort to British servicemen. One of these projects was the Princess Mary's 1914 Christmas Gift Fund, through which Christmas gift tins were sent to all British servicemen at the front. She became honorary president of the British Girl Guide Association in 1920, a position she held until her death. In 1926, she became the commandant-in-chief of the British Red Cross Detachments. On 28 February 1922, she married Viscount Lascelles, the elder son of the 5th Earl of Harewood. On 1 January 1932, George V declared that his only daughter should bear the title Princess Royal.

The Princess Royal was particularly close to her eldest brother, the Prince of Wales, who subsequently became Edward VIII and Duke of Windsor. After the abdication crisis, she and her husband went to stay with the former king, at Enzenfeld Castle, Austria. Later, in November 1947, she allegedly declined to attend the wedding of her niece, Princess Elizabeth to Phillip Mountbatten to protest the fact that the Duke of Windsor had not been invited. She gave ill health as the official reason for her non-attendance.