 Xiao's was one of the portraits.Later that year, Li Chengqian, fearful that Emperor Taizong was considering replacing him with his younger and more favored brother Li Tai the Prince of Wei, plotted with the general Hou Junji to overthrow Emperor Taizong.When the plot was discovered, Emperor Taizong commissioned Xiao, along with Zhangsun, Fang, Li Shiji, and officials from the supreme court, the legislative bureau, and the examination bureau, to investigate.