《汉书·传·外戚传下》
飞燕有个妹妹也被召进宫来，姐妹二人都被封为徒仔，其贵幸超过整个后宫。
有女弟复召入，俱为婕妤，贵倾后宫。
Feiyan had a younger sister who was also summoned to the palace, and the two sisters were both named concubines, their favor exceeding that of the entire harem.