But it did mean that, after some years, I was able to realise that dream of becoming a doctor. Not quite the type I once envisaged, no, but one rather desperately required. I became a doctor of psychotherapy, now retired. I worked all my life with children, trying to put back together the pieces of broken minds. In so doing, I went someway to nurse my own. And one other thing I achieved, of lesser importance but no less meaningful: I overcame my fear of water! I used to swim every day during the summer. Each time I did, I thought of you and how you would have been proud. It made me smile to think of it.

I never had any more children of my own. My marriage to Tomas was short-lived and not a happy one. He was sent to the front before the end of our first year together and did not see his twentieth birthday. I had no interest in remarrying then. I focused first, on survival, and second, on my work. But, much later in life, long after I’d given up on ever again finding personal happiness, I met Max, an older, uncomplicated man, with the gentlest of hearts. We married and we were happy. He died twelve years ago.

And what of the others? Vati committed suicide when Berlin fell. Mutti never stopped believing in the Nazi dream, nor in the greatness of her husband. Eventually, she too died, of a broken heart. I’m so grateful that Karl never saw the horrors which were to come. I never knew what became of Hilda and little Sophie. After the war, I moved away to a small town far from Leipzig.

And your family, Walter? I think of them often. I know they were all, in the end, sent to Buchenwald and from there, I suspect, on to Auschwitz or Theresienstadt. I cannot imagine the pain and suffering they must have gone through. It haunts me to this day.

But most of all I remember Erna and her parents, without whom I would not be sitting here today. All three of them, beacons of goodness, perished in a camp. One day in the autumn of 1942 I went to their flat and they were gone, the place turned upside down. There was no warning and not a day goes by when I don’t think of my wonderful friend, Erna, and her halo of auburn hair, destined to be forever young in my memory.

Nor shall I ever forget the day I had to send Stanley away. I think of the thousands of other mothers who did the same, feeling their pain as they sent their own precious children into the unknown, desperately entrusting them to strangers. And I think of the countless parents who were unable to save their children’s lives.

And never for one day will I forget what I once was, when I was one of the believers. It was you, dear Walter, who first turned my head and made me see that people are people, regardless of anything else. It was you who made me understand that we all have immense capacity for both good and evil, that we must stand up and speak out against those who preach hate. Every day that I live I wish the Nazis had never come to power, that the camps had never existed. Every day I live with the shame and guilt of the part I once played and will do so until my dying day.