Lady Diana's 11-Great Uncle. HM Juan Carlos' 11-Great Grandfather. Philippe of Belgium's 11-Great Grandfather. Grand Duke Henri's 11-Great Grandfather. HM Margrethe II's 11-Great Grandfather. HM Beatrix's 10-Great Grandfather. HM Constantine II's 11-Great Uncle. HM Carl XVI Gustaf's 11-Great Grandfather. HM Harald V's 10-Great Grandfather.