HRH Charles's 10-Great Grandfather. HM Juan Carlos' 8-Great Grandfather. HM Manuel II's 7-Great Grandfather. HM Margrethe II's 9-Great Grandfather. HM Beatrix's 8-Great Grandfather. HM Constantine II's 9-Great Grandfather. HM Carl XVI Gustaf's 9-Great Grandfather. HM Harald V's 9-Great Grandfather. Ksr Wilhelm II's 7-Great Grandfather.