"My Uncle Jonathan sent me this very special Fed Ex package because I'm so good at keeping secrets. I'm in charge of keeping the sparkly ring inside the box a secret from his girlfriend, Katherine. That's why he sent it to my house instead of his own. I'm going to give it to him to give to her this weekend. I'm so happy she's going to be my aunt!"
p.s. Katherine said yes! I'm so glad I could help out Uncle Jonathan with his big surprise:)