Mirjam and Ludwik were both born into prosperous families. Both had happy early childhoods. Like millions of others, both had their lives shattered by the second world war. Mirjam was caught with her mother and sisters in the occupied Netherlands, living under increasingly oppressive Nazi rule before being moved to the Dutch holding camp for Jews at Westerbork, and then Belsen. Ludwik, who grew up in Poland, was exiled to eastern Kazakhstan by the Soviets with his mother, where they lived through a Siberian winter with little food and no shelter. Both somehow survived through a combination of willpower, help...