sentences:  He was the heir presumptive to the headship of the deposed House of Hohenzollern from the death of his father to 20 January 2013, when Georg Friedrich fathered twin sons, relegating Christian-Sigismund to a more remote place in the Line of succession to the former German throne.His two eldest brothers, Prince Friedrich Wilhelm (1939-2015) and Prince Michael (1940-2014) married commoners in the mid-1960s and renounced their historical rights as Prussian princes.In 1975 his brother Prince Louis Ferdinand Jr. (1944-1977), dynastically wed a mediatised countess, Donata Countess of Castell-Rüdenhausen (1950-2015), but died accidentally during German military maneuvers two years later, leaving an only son, Georg Friedrich, as heir to the Hohenzollern legacy.