Her mother, Kenshi was from the lower class of the FUJIWARA clan; her father, Kinhira was from the Saionji family which had been succeeding the important position in charge of coordination between the Imperil court and the Kamakura bakufu (Japanese feudal government headed by a shogun) in Kanto Moshitsugi; Kinhira dealt with critical affairs of the Imperial court as Kanto moshitsugi.
母兼子は藤原氏の下級貴族の出自だったが、父公衡の西園寺家は代々朝廷・鎌倉幕府間の連絡調整を担当する関東申次の要職を継承しており、公衡も関東申次として朝廷政務の枢要に当たっていた。