In May 1940, as the Nazis invaded the Netherlands, my mother, then 21 years old, escaped from the country in a trawler hijacked by her father, a self-made fish merchant. Her father, one of nine, asked all his wider family to join them on the journey to England. None did: they were all slaughtered in the Holocaust. My father, who grew up in Vienna, left in 1937, at the age of 27. He then came to England, where he was...