Princess Herzeleide of Prussia Prussian princess (1918–1989) (1918–1989) Parents Countess Ina Marie von Bassewitz Prince Oskar of Prussia Children Benigna Prinzessin Biron von Curland Michael Biron von Curland Ernst-Johann Biron, Prince of Courland Siblings Prince Oskar of Prussia Prince Burchard of Prussia Prince Wilhelm-Karl of Prussia Partners Karl Peter Biron von Curland