In 619, Yuwen Huaji was captured and executed by one of the rebel leaders, Dou Jiande the Prince of Xia. Dou treated Empress Xiao with kindness and respect while giving a proper mourning for Emperor Yang. Subsequently, the Princess Yicheng requested that Dou send Empress Xiao to her, and Dou did so, along with Emperor Yang's daughter Princess Nanyang and the head of Yuwen Huaji. An emissary was sent to welcome her and the former Empress traveled to Tujue, North of the Great Wall. While she was in Tujue, one of Yang Jian's consorts gave birth to a posthumous son, Yang Zhengdao (), whom she raised, and whom Ashina Duojishi subsequently created the Prince of Sui, assigning to him as his subjects the refugees from Sui. She went to live in Dingxiang. During the years, Tujue's khans continued to use Yang Zhengdao as a magnet to attract the people to surrender, in competition to Tang Dynasty, established by the Sui general Li Yuan (Emperor Gaozu).