About Princess Mary, Duchess of Gloucester and Edinburgh
Princess Mary, Duchess of Gloucester and Edinburgh (25 April 1776 – 30 April 1857) was the eleventh child and fourth daughter of King George III and his consort Charlotte of Mecklenburg-Strelitz. She married her first cousin, Prince William Frederick, Duke of Gloucester and Edinburgh, when both were 40, and was his widow in later life. In her last years, her niece Queen Victoria was on the throne as the fourth monarch during Mary's life, after her father and two of her brothers, George IV and William IV. Dying aged 81 at Gloucester House, Weymouth, Mary was the longest-lived and last survivor of George III's fifteen children (thirteen of whom lived to adulthood). == Early life and family == Mary was born on 25 April 1776, at Buckingham Palace, London. Her father was the reigning British monarch, George III. Her mother was Queen Charlotte, the daughter of Charles, reigning Duke of Mecklenburg-Strelitz. Mary was baptised on 19 May 1776, in the Great Council Chamber at St. James's Palace, by Frederick Cornwallis, the Archbishop of Canterbury. Her godparents were: Landgrave Frederick of Hesse-Cassel (her first cousin once-removed, for whom the Earl of Hertford, Lord Chamberlain stood proxy) The Duchess of Saxe-Gotha-Altenburg (wife of her first cousin once-removed, for whom the Duchess of Argyll, Lady of the Bedchamber to the Queen, was proxy) Princess Charles of Mecklenburg-Strelitz (her third cousin once-removed, for whom the Dowager Countess of Effingham, Lady of the Bedchamber to the Queen, stood proxy). The king was a devoted father, finding time to regularly visit the royal nursery. Engaging in active play with his young children, he behaved quite informally in contrast to the dignified Queen Charlotte, who had more difficulty abandoning the formal behaviour expected of their class.
Biography source: Wikipedia. The profile adds birthday-specific historical context from the Celebs Birthday Today editorial database.