Well this is a lovely surprise. The annual Evening Reception for the Diplomatic Corps was held tonight, November 8, at Buckingham Palace, and Prince William and Kate Middleton joined Queen Elizabeth, Prince Philip, Prince Charles, and Camilla, Duchess of Cornwall for the white tie event.
Here are some photos of some royals doing stuff: Queen Elizabeth II; Prince Charles & Camilla, Duchess of Cornwall; Prince Oscar; and Prince Carl Philip & Princess Sofia.
The Duke and Duchess of Cambridge, Prince William and Kate Middleton, attended their first ever State Banquet this evening, October 20, at Buckingham Palace in honor of the President of China. The Cambridges joined Queen Elizabeth II and Prince Philip in honoring President Xi Jinping and Madame Peng Liyuan. *Updated with more photos*