In the fall of 615, when Emperor Yang of Sui was visiting Yanmen Commandery on the northern frontier, the khagan launched a surprise attack on the area, overrunning most of its Chinese settlements.
Warned by the khagan's wife Princess Yicheng — a member of the imperial family who had been well treated by Empress Xiao during an earlier visit — the emperor, empress, and their entourage escaped to the commandery seat at present-day Daixian.
Emperor Yang put Xiao Yu and Pei Ju in charge of planning the military counteroffensive, but was only able to get the siege lifted after he followed the advice of the empress's brother Xiao Yu and sent messengers to Princess Yicheng, who was directing military affairs at the Turkic capital in her husband's absence.
After Chuluo's death in June, she refused to marry Ashina Momo (阿史那摸末, 607 - 649, was titled Yushe shad (郁射設) and eventually married to someone of imperial Li (李) clan[5]), claiming he was weak.
After refusing Yushe Shad, she finally wed to Illig Qaghan in 620, yet another step-son.