The Origin of a Novel
It started, oddly enough, as an insomnia cure. I found that when I had trouble falling asleep, daydreaming didn't work—because I am the hero of my own daydreams, and so too closely involved with them. It occurred to me that if instead I plotted out a novel, I would have sufficient distance from my characters to be able to drift off.
It worked. Over a period of many months I plotted out parts of several novels and, eventually, all of one. House rules at the time required me, when putting one of our children to bed, to make up and tell three stories. I mentioned to my daughter that I had written a novel in my head and she suggested I tell her that instead.
The problem with telling my daughter stories is that she remembers them better than I do. The result in the past, when I was doing a long series of linked fantasy stories, was that just when I thought I had the characters in an almost impossible situation she would point out that the magic item they obtained three months earlier was precisely the thing to get them out of it. So this time, every evening after putting her to bed, I wrote an outline of what I had told her. As I got near the end I started thinking seriously of turning it into a novel. I wrote the final scene, liked it, and went back and wrote the whole first draft in a month or two. It was so much fun that, during that time, I played almost no computer games.