우문술
By 600, Yang Guang's older brother Yang Yong had lost the favors of Emperor Wen and Empress Dugu—over his wastefulness (which displeased Emperor Wen) and his having many concubines (which displeased Empress Dugu). Yang Guang, by contrast, pretended to be frugal and loving only Princess Xiao. (It was written that Yang Guang did have concubines, but he pretended that he did not, and that he forced his concubines to have abortions if they became pregnant.) Yang Guang further inflamed Empress Dugu by informing her that she believed that Yang Yong was determined to kill him eventually. Empress Yang thus resolved to remove Yang Yong. Yang Guang further had his associate Yuwen Shu persuade Yang Su's brother Yang Yue () that, because Yang Su's relationship with Yang Yong was not good, that their family would be in peril should Yang Yong succeed Emperor Wen. Finally, Yang Guang also had Yang Yong's associate Ji Wei () accuse Yang Yong of plotting treason. Emperor Wen had Yang Su investigate, and Yang Guang and Yang Su manufactured evidence against Yang Yong. Emperor Wen deposed Yang Yong and replaced him with Yang Guang, putting Yang Yong under house arrest under Yang Guang's watch. Yang Guang later prevented Yang Yong from all attempts of seeing his parents again.