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.

The picture, which also shows a stack of other anniversary cards, was snapped in the Oak Room at Windsor Castle three days ahead of the couple’s anniversary.

For the photo, the Queen chose an important piece of jewelry. According to People, she donned the Chrysanthemum Brooch, which she wore on her honeymoon as well as in official images from her and Philip’s 60th anniversary.

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