Professional Cup-stackers?

This may be a surprise to you, but cup-stacking is a sport. A real competitive sport that quite a few people are engaged in. Anyway, Rachel and Gracie learned how to cup stack (with a bunch of paper cups), even though they are really little. It is so cute to see Gracie carefully putting one cup on top of the other. I can't wait until these guys are older and they can learn the tricks to cup-stacking. I don't know if they'd really like it since they wouldn't be allowed to knock them down into a mess, though. Here are some cute pictures of them and their cups: