"Growing up in Paris, the daughter of a German mother and an Irish father, Svenja O'Donnell knew little of her family's German past. All she knew was that her grandmother and her mother had fled their home city of Königsberg in the far east of Germany near the end of World War II, never to return. But everything changed when O'Donnell traveled to Königsberg -- now known as Kaliningrad, and part of Russia -- and called her grandmother, who uncharacteristically...