Pei Du
Around new year 823, when Emperor Muzong was at a polo match, there was a mishap where a eunuch fell from his horse—causing much shock for Emperor Muzong and leading to a debilitating stroke, causing him to be unable to rise. Many officials, including the leading officials Pei Du and Li Fengji requested that he create a crown prince, and Emperor Muzong, after initially not responding, created Li Zhan crown prince.