Before my 19-year-old son di3d, he donated his heart to an 18-year-old girl — after the transplant, her mother handed me a letter from my son that began, “Mom, there’s something you need to know about her.”

And then, in the June — because he was nineteen and he had just been told that his father had given him the thing that was killing him — he did something I did not know about.

He sent off one of those genealogy kits. The ones you see advertised. Spit in a tube, find your ancestors.

He did it, he wrote, to find out if there was anybody else out there who might have it and not know.

And three weeks later the site told him he had a half-sister. Living. Forty miles away.

What he did about it.

He contacted her himself, in the July, through the site’s messaging. Without telling me.

And they met eleven times between the July and the December.

Eleven. In cafés, mostly. Once in a car park at a garden centre because it was raining and neither of them could face going in.

He never mentioned her. Not once, in five months. I thought he was at his friend Danno’s.