HRH Charles's 16-Great Grandfather. PM Churchill's 15-Great Grandfather. Lady Diana's 17-Great Grandfather. HRH Albert II's 17-Great Grandfather. HM Juan Carlos' 16-Great Grandfather. Philippe of Belgium's 17-Great Grandfather. HM Manuel II's 15-Great Grandfather. HM Margrethe II's 16-Great Grandfather. HM Beatrix's 15-Great Grandfather. HM Constantine II's 16-Great Grandfather. HM Harald V's 16-Great Grandfather. Ksr Wilhelm II's 14-Great Grandfather.