HRH Charles's 16-Great Grandmother. HM Juan Carlos' 15-Great Grandmother. Philippe of Belgium's 15-Great Grandmother. HM Manuel II's 14-Great Grandmother. Grand Duke Henri's 15-Great Grandmother. HM Margrethe II's 14-Great Grandmother. HM Beatrix's 14-Great Grandmother. HM Constantine II's 15-Great Grandmother. HM Carl XVI Gustaf's 15-Great Grandmother. HM Harald V's 14-Great Grandmother. Ksr Wilhelm II's 13-Great Grandmother. `Red Baron' Richthofen's 12-Great Grandmother.