"I thought about my father, about his love for Sparrow and Zhuli. How many notes are there in Bach's Goldberg Variations? In Shostakovich's Fifth Symphony? How many words are each of us granted over the course of a lifetime? That night, I began writing down my memories of Ai-ming. I wrote slowly at first, and then the story quickened. I hoped that writing would allow me, finally, to keep the promise I had made to Ma."