Book of Zhou
Emperor Xuan died in summer 580, and Empress Yang's father Yang Jian became regent. Empress Yuan became a Buddhist nun with the name of Huasheng, and she outlived Yang Jian's subsequent Sui dynasty. According to both the "Book of Zhou" and "History of Northern Dynasties", she was still alive as of the reign of Emperor Taizong of Tang (626-649), but nothing further was recorded in either of those two official histories about her.