 After disappearing during a mission near the Belarusian city of Orsha, Gustav Albrecht was declared missing in action.His family did not seek to have him declared dead until after the birth of his grandson and heir eventual Prince Gustav on 12 January 1969; 29 November 1969 is listed as the official date of death for Gustav Albrecht.He is alternately known as Gustav Albrecht Prinz zu Sayn-Wittgenstein-Berleburg.