In a certain social group, some birthday party invitations are more impressive than others. As Prince George celebrates his thirteenth birthday, school parents at Lambrook School—where Prince George, Princess Charlotte, and Prince Louis have attended school for the last few years—have revealed Prince William and Princess Kate are incredibly “hands-on” at their children’s birthday parties. While it's hard to imagine a low-key birthday party for the future King of England, the Prince and Princess of Wales are known for hosting down-to-earth children’s parties at their family home.