HRH Charles's 16-Great Aunt. HM Juan Carlos' 16-Great Aunt. Philippe of Belgium's 16-Great Aunt. Grand Duke Henri's 16-Great Aunt. HM Margrethe II's 16-Great Aunt. HM Beatrix's 16-Great Aunt. HM Harald V's 15-Great Aunt. Ksr Wilhelm II's 15-Great Aunt.