 Paul's hometown of Neustettin, then part of Germany, became Polish territory after the Second World War and is now called Szczecinek.In 1910, Konrad married the painter Gertrud Kressner (1879 - 1974).They had a daughter Ortrud Knopp (1911 - 1976), with the grandchildren Willfried Spohn (1944 - 2012), Herbert Spohn (*1946) und Wolfgang Spohn (*1950), and a son Ingolf Knopp (1915 – 2008), with the grandchildren Brigitte Knopp (*1952) and Werner Knopp (*1954).