Reading back through old journals, I found this from January 3, 2003:

Nathaniel really moved me this afternoon. He was “predicting” and predicted I’d die when I was 110. I said that sounded just fine to me, that’d be a good long life. He asked how old he’d be when I was 110. I said 78.

He said that’s when he would die, because he didn’t want to live longer than me. I insisted he had to live longer, at least past 100, and that it was natural for a parent to die before his child because the parent is older. He asked when I thought I would die, and I said I had no idea, but I hoped it’d be a long, long time.

He gave me a very close hug.