As children we did not grow up steadily, one day at a time. Occasionally, we would leap forward. Getting separated from our mother in the supermarket and—holding panic at bay—finding her on our own could make us instantly feel a year older. It is the same way we felt when we rode off alone on a bicycle for the first time.

While most of these experiences left me exhilarated, there was one leap forward that produced less welcome emotions. When I was eight years old I began to consider the possibility that Santa Claus was not real. Embracing this suspicion made me feel grown up, very suddenly and also very unhappily. Leaving behind a belief in Santa meant I would never again experience the enchantment that accompanied the days leading up to Christmas. The exquisite, almost unbearable anticipation of a fairy tale coming to life, a fairy tale that included me, would be gone forever.

This didn't feel like growing up. This felt like losing something—like being thrown out of the land of miracles and hearing the gates close behind me.

I wanted back in. Fortunately, the Polar Express pulled up to my house that Christmas, taking me on a trip that did lead me back. There is a seat on the train for you.