How did David end up in the concentration camp?

David's parents were both alive when he was born. His mother escaped Germany, his father was killed, and David was placed in a Nazi concentration camp.

One night the police arrested them - all three of them, her hus- band, herself and their little boy who was then only a year old - he was the one who was called David just like you, and whom I never saw . . . They killed her husband and the child, and Edith only got away be- cause one of her guards knew her and was in love with her. He got papers for her and smuggled her across the frontier, and now she lives at home in Denmark and is as . . . well, as well as you can be when you've once been through great unhappiness.