Tian Chengsi
In 778, for reasons unclear in history, Li Baochen briefly assumed his old surname of Zhang. However, in 779, he became apprehensive about having done so, and, with Emperor Daizong's permission, reassumed the imperial surname of Li. Also in 779, when Tian Chengsi died, it was at the urging of Li Baochen that Emperor Daizong officially approved Tian Chengsi's selected successor, his nephew Tian Yue, as Tian Chengsi's successor.