British royals mark Garter Day

Queen Elizabeth II attends the annual Order of the Garter Service at St George's Chapel, Windsor Castle on June 13, 2011, in Windsor, England.

Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge attend the annual Order of the Garter Service at St George's Chapel, Windsor Castle on June 13, 2011, in Windsor, England.

Prince Edward, Earl of Wessex, Prince Charles, Prince of Wales, Prince William, Duke of Cambridge, Sophie, Countess of Wessex, Camilla, Duchess of Cornwall and Catherine, Duchess of Cambridge attend the annual Order of the Garter Service at St George's Chapel at Windsor Castle on June 13, 2011, in Windsor, England.

Prince William attends the annual Order of the Garter Service at St George's Chapel, Windsor Castle, on June 13, 2011, in Windsor, England.

From left, Camilla, Duchess of Cornwall, Catherine, Duchess of Cambridge, Princess Anne, Princess Royal and Prince Andrew, Duke of York leave St George's Chapel at Windsor Castle after attending the annual Order of the Garter Service on June 13, 2011, in Windsor, England.

Princess Eugenie, left, and Princess Beatrice share a joke as they attend the annual Order of the Garter Service at St George's Chapel, Windsor Castle on June 13, 2011, in Windsor, England.

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Camilla, Duchess of Cornwall, left, and Catherine, Duchess of Cambridge watch the Garter Service pass by on June 13, 2011, in Windsor, England.

Prince William arrives for the Garter Service at St George's Chapel in Windsor Castle on June 13, 2011, in Windsor, England.

Queen Elizabeth II is watched by Catherine, Duchess of Cambridge as she proceeds during the Order of the Garter Service on June 13, 2011, in Windsor, England.

Princess Anne, Princess Royal, right, and her brother Prince Edward, Earl of Wessex attend the annual Order of the Garter Service on June 13, 2011, in Windsor, England.

Queen Elizabeth II and Prince Philip, Duke of Edinburgh arrive to attend the annual Order of the Garter Service at St George's Chapel in Windsor Castle on June 13, 2011, in Windsor, England.

Prince William and his father, Prince Charles, proceed during the Order of the Garter Service on June 13, 2011, in Windsor, England.

Queen Elizabeth II attends the annual Order of the Garter Service at St George's Chapel, Windsor Castle, on June 13, 2011 in Windsor, England.

Prince Philip, Duke of Edinburgh arrives for the Garter Service at St George's Chapel in Windsor Castle on June 13, 2011, in Windsor, England.

Queen Elizabeth II and Prince Philip, Duke of Edinburgh walk down the steps of St George's Chapel, Windsor Castle following the annual Order of the Garter Service on June 13, 2011, in Windsor, England.

Former Prime Minister Margaret Thatcher stands on the steps of St George's Chapel at Windsor Castle following the annual Order of the Garter Service on June 13, 2011, in Windsor, England.

Prince Charles and his son Prince William attend the annual Order of the Garter Service at St George's Chapel, Windsor Castle, on June 13, 2011, in Windsor, England.

Queen Elizabeth II and Prince Philip, Duke of Edinburgh leave the Garter Service at St George's Chapel in Windsor Castle on June 13, 2011, in Windsor, England. The Order of the Garter is the senior and oldest British Order of Chivalry, founded by Edward III in 1348. Membership in the order is limited to the sovereign, the Prince of Wales, and no more than 24 members.

Catherine, Duchess of Cambridge leaves the Garter Service in a carriage at St George's Chapel in Windsor Castle on June 13, 2011 in Windsor, England.

Prince William, right, waves to crowds beside Catherine, Duchess of Cambridge, Prince Charles and Camilla, Duchess of Cornwall as they leave the annual Order of the Garter Service at St George's Chapel, Windsor Castle on June 13, 2011, in Windsor, England.

Princess Alexandra leaves the Garter Service at St George's Chapel in Windsor Castle on June 13, 2011, in Windsor, England.

Prince Edward, Earl of Wessex and Sophie, Countess of Wessex attend the annual Order of the Garter Service at St George's Chapel, Windsor Castle on June 13, 2011, in Windsor, England.

Catherine, Duchess of Cambridge leaves the Garter Service in a carriage at St George's Chapel in Windsor Castle on June 13, 2011, in Windsor, England.

Camilla, Duchess of Cornwall, left, and Catherine, Duchess of Cambridge watch the Garter Service pass by on June 13, 2011, in Windsor, England.

Catherine, Duchess of Cambridge, left, and Camilla, Duchess of Cornwall wave to crowds beside Prince William and Prince Charles as they leave the annual Order of the Garter Service at St George's Chapel, Windsor Castle on June 13, 2011 in Windsor, England.

From left, Prince Charles, Prince Andrew, Prince Edward and Princess Anne arrive to attend the annual Order of the Garter Service on June 13, 2011, in Windsor, England.

Catherine, Duchess of Cambridge, left, waves to crowds beside Prince William, Prince Charles and Camilla, Duchess of Cornwall as they leave the annual Order of the Garter Service at St George's Chapel at Windsor Castle on June 13, 2011, in Windsor, England.

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