One way to remain unfinished is to stop. the other is to go on.

I'm drawn to intergenerational tension, and it must have been strong in the 1920s: I wondered how Louise's [Brooks] generation of flappers appeared to the women who came of age at the beginning of the century - wearing corsets, long skirts, and high collars.

The young can exasperate, of course, and frighten, and condescend, and insult, and cut you with their still unrounded edges. But they can also drag you, as you protest and scold and try to pull away, right up to the window of the future, and even push you through.

While I was writing the book, I went to see Louise Brooks's most famous film, Pandora's Box, at the Tivoli in Kansas City, and it was a lovely experience. You can watch old silent films on DVD or even on YouTube, but it was a different feeling watching her up on the big screen, seeing the film the way people saw it all those years ago.

The thing that got me about the Orphan Trains was that the experiences were so varied. Some of the kids went from neglect and hunger in New York to loving farm families who couldn't wait to fatten them up, who gave them medical care, an education, affection. And some of the kids became the victims of terrible cruelty, and more hunger, and more neglect - it all depended on who adopted them off of the train.

You could push people away, past their limits, even accidentally, and then it was just too late to get them back

I know that sometimes when you are really worried about something, it ends up not being nearly as bad as you think it will be, and you get to be relieved that you were just being silly, worrying so much over nothing. But sometimes it is just the opposite. It can happen that whatever you are worried about will be even worse than you could have possibly imagined, and you find that you were right to be worried, and even that, maybe, you weren't worried enough.