HRH Charles's 10-Great Grandmother. HM Juan Carlos' 11-Great Grandmother. Philippe of Belgium's 11-Great Grandmother. Grand Duke Henri's 11-Great Grandmother. HM Margrethe II's 10-Great Grandmother. HM Beatrix's 10-Great Grandmother. HM Constantine II's 10-Great Grandmother. HM Carl XVI Gustaf's 10-Great Grandmother. HM Harald V's 10-Great Grandmother. Ksr Wilhelm II's 8-Great Grandmother.