While "Heike Monogatari" (The Tale of Heike) depicts FUIWARA no Hoshi as a daughter of FUJIWARA no Korezane (also known as Torikai Chunagon (vice-councilor of state)), who was later adopted by FUJIWARA no Kunitsuna as his daughter, descriptions in "Sonpi Bunmyaku" (a text compiled in thefourteenth century that records the lineages of the aristocracy) and "Gukansho" (Jottings of a Fool) make it more likely that she was Kunitsuna's own daughter.
『平家物語』には藤原伊実（惟実）（鳥飼中納言）の娘で、藤原邦綱の養女となったとあるが、『尊卑分脈』や『愚管抄』の記述から邦綱の実子と考えられている。