Under the pressure of these dynasties, the Sung dynasty made a fictitious blood relationship (for example, diplomatic relations assuming Sun as the older brother and Liao as the younger brother) with them.
宋は圧迫されて北方の帝国と国家同士の擬制的な血縁関係（たとえば宋を兄、遼を弟とするような外交関係）を結んだ。