And they’re off! Prince William and his best man, Prince Harry, have arrived at Westminster Abbey. Both are wearing their RAF uniforms—William in Irish Guard red and Harry in the Blues and Royals formal dress. Both topped their uniforms ff with their medals, William’s one and Harry’s two. Kate Middleton's mother and younger brother, James, arrived at the Abbey a few minutes after William and Harry, followed by Prince Charles and Camilla and Queen Elizabeth and the Duke of Edinburgh. Carole Middleton is wearing a Cassandra Vinograd dress while Camilla wore a Anna Valentine dress with a Philip Treacy hat. As predicted by oddsmakers, Queen Elizabeth wore a yellow hat. They join the approximately 1,900 guests who have been streaming in to the Abbey, including some A-listers Elton John, David and Victoria Beckham, and Prime Minister David Cameron. Prince Harry’s on-again, off-again Chelsy Davy arrived in an Alberta Ferretti dress, one of two dresses she will wear Friday.