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.

He looked exactly like the officer that entire family has been pointing at since he was about nineteen — and like the man in four photographs on the wall of that hall, three of which are his father.

Next to him was a woman of about thirty in a long green dress, with her hand resting on his arm in the way you do when you have been told something is about to happen.

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.