Prince George, Princess Charlotte and Prince Louis are quite the crafty trio.

The royal siblings gave a homemade card to their great-grandparents, Queen Elizabeth II and Prince Philip, in honor of their 73rd wedding anniversary on Friday.

The Queen, 94, and Philip, 99, were photographed smiling while looking at the children’s homemade card, which features a big “73” and colorful circles on the front.

George, 7, Charlotte, 5, and Louis, 2, are Prince William and Kate Middleton’s three children