Yang Xiu
By 602, Yang Guang was concerned that his brother, Yang Xiu the Prince of Shu, who as the commandant at Yi Province (roughly modern Chengdu, Sichuan) was in control of the modern Sichuan and Chongqing region, would eventually make trouble for him. He had Yang Su collect evidence of Yang Xiu's wastefulness and inappropriate behavior. Emperor Wen summoned Yang Xiu back to the capital, and had Yang Su investigate. Both Yang Guang and Yang Su manufactured additional evidence against Yang Xiu, and Yang Xiu was reduced to commoner rank and put under house arrest.