Britain's Prince William, the Duke of Cambridge, and his wife Catherine, Duchess of Cambridge, as she was released from King Edward VII hospital in central London earlier today. Leon Neal/AFP/Getty Images hide caption
Prince William
April 29, 2011: Their Royal Highnesses Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge kiss on the balcony at Buckingham Palace after their wedding. Peter Macdiarmid/Getty Images hide caption
A special cake re-enacting the scene of Prince William, Duke of Cambridge's wedding in 2011 where he drove the car with his wife the Catherine, Duchess of Cambridge, as he attends a reception prior to the annual October Club dinner in aid of the St Giles Trust on Wednesday night. WPA Pool/Getty Images hide caption
Britain's Duchess of Cambridge during her speech today at a children's hospice in Ipswich, England. Kirsty Wigglesworth/AP hide caption
President Barack Obama and first lady Michelle Obama talked with Prince William, duke of Cambridge and Catherine, duchess of Cambridge at Buckingham Palace earlier today (May 24, 2011). Toby Melville/WPA Pool/Getty Images hide caption
Kate, now the Duchess of Cambridge, and little Grace van Cutsem. Matt Dunham/AP hide caption
Their Royal Highnesses Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge kiss on the balcony at Buckingham Palace after their wedding. Peter Macdiarmid/Getty Images hide caption
A fan holds British Union Jack flags as people gather to watch the wedding of Britain's Prince William and Kate Middleton on big screens in Hyde Park in central London. Carl Court/AFP/Getty Images hide caption
British Union Jack flags fluttered in the wind next to Big Ben, in London, on Thursday (April 28, 2011). Damien Meyer /AFP/Getty Images hide caption
Prince William's parents, Charles and Diana, on their wedding day — July 29, 1981. If it rains Friday, William and Kate won't be able to use an open carriage. Hulton Archive/Getty Images hide caption
British Union Jack flags are all over Regent Street in London, as the city prepares for Friday's wedding. Adrian Dennis /AFP/Getty Images hide caption