On 9 November1938 Nazis led attacks on Jewish homes and businesses across Germany. Because of the number of windows that were smashed it would be remembered as the 'night of broken glass' or Kristallnacht. Writer and artist Nora Krug investigated what happened in her hometown of Karlsruhe that night and wrote a book, Heimat, about her family's wartime history. She has been speaking to Kirsty Reid about what she uncovered.