My grandfather's whole family were murdered – but he found a way to forgive the killers

After 12 of his relatives were killed in a single night, where was his anger and pain? And what does his refusal to permit himself these feelings mean for me?

I don't know when I first heard my grandfather's story. But I do remember the little green book with the white cross on it. The book was kept in a black steel cabinet in our living room, one that was usually locked, its contents mysterious. There must be important things in there, I thought, that were not for me to see.

My paternal grandparents were part of my childhood; my sister and I called them Oma and Opa and paid them regular visits, but we knew very little about our mother's parents. They were long dead: my grandmother in 1972, my grandfather in 1979, six years before my birth. The only proof of their existence was a faded black-and-white photo embedded in a glass hemisphere, which my mother kept on her bedside table. In the picture, my grandmother is wearing a high-necked dress and a pearl necklace, and my grandfather a suit and tie, their faces radiating severity. They looked, to my child's eyes, the way I imagined people from the olden days did; they were from a different world, a different time. I knew my grandmother had been a nurse, and my grandfather a pharmacist, and that they had run a retirement home together near Bremen in Germany. We never visited their grave.