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 the fourth is the one I did not know about until Christmas Day.

In the April of 2019, Eudora Vail flew to Texas.

She did not write ahead because I had told her not to contact us. She came, at seventy years old, on her own, and she sat in a hired car in the car park outside my children’s daycare for about four hours.

She watched four two-year-olds come out at the end of the day in a line holding a rope, the way they do it at that age.

With a woman called Rosemary, who collected them for me on Thursdays for about four years and who has no idea any of this happened.

And she did not get out of the car.

Because a woman had told her, in four words, on a telephone, never to contact us again — and Eudora Vail is from a world