My ex-husband invited the former wife he believed was still childless and miserable to his family’s Christmas at their military estate. He never imagined I would arrive on a government tactical helicopter — with four eight-year-olds who had his face.

And in his other hand, open, was a small velvet box.

He had been about four seconds from proposing to that woman in front of a hundred people on Christmas Day.

Which I did not know. I want that said clearly, because about four people have asked me whether I timed it.

I did not know she existed. I did not know there was a proposal. I landed a helicopter two hundred yards from that house at twenty to ten in the morning and walked into the middle of it by pure accident.

For one moment he looked irritated. Somebody had come in late and made a noise and he had a thing in progress.Then he saw it was me.

And something went across that man’s face that I had been waiting eight years to see.

I had pictured it about four hundred times. The real one was faster than the pictured one and it was gone in about a second, and I have thought about that single second considerably more than I expected to.