She was born in Iimori-mura, Yoka no sho, Saga-gun, Hizen Province as the second daughter of the couple of Tsunenobu ISHII (a senior vassal of Takanobu RYUZOJI) and a daughter of the Kuro clan.
龍造寺隆信の重臣石井常延・黒尾氏夫妻の次女として、肥前国佐嘉郡与賀庄飯盛村に生まれる。