Do you remember taking roly poly tumbles down hills? Topography in my childhood was constantly assessed on the basis of its suitability for climbing to the top and rolling back down. There's a wonderful sense of abandon to a good hill-roll, completely surrendering yourself to the forces of gravity while tumbling in a disorienting swirl of sky and grass and sky and grass until you land at the bottom, puffed and dizzy and proud. Then you brush the grass and twigs off your clothes, and run to the top of the hill to try again.

When did I stop rolling down hills? When do adults stop playing in general? And why do we choose to stop doing something that is so harmless and so much fun?

I don't want to just watch Madeleine play. I don't want her to have to beg me to join in. I am going to make a conscious effort to rediscover playful, childlike me.

This Schweppervessence ad premiered on Australian television on Sunday night, during Downton Abbey. It's like childhood, but better: grown men and women tumbling through an alpine landscape, over snow, fields, forests and finally a waterfall.

In one sense, I fear that sharing an ad with you guys is buying into commercialism but, honestly, I'm just thankful to the folks at Schweppes for making me happy. So I have to give them props. What a joyful, creative minute they gave me!

ps. Once upon a time I made up a story that if you rolled down the hill in our front yard with your eyes closed, when you got to the bottom you would be in a different world. I played this game with my friend Elise when I was about seven or eight. When we got to the bottom of the hill, all dizzy and disoriented, I said, "Look! We are in an ancient world! Can you see the pyramid?" (I was pointing at the swing set). That game was short-lived, since the next time I knocked on Elise's door and asked her mother if she could come out and play, her mother said, "Elise isn't allowed to play with liars." So much for imagination, huh?