"Shotetsu monogatari" (Tale of Shotetsu) also states that 'Kunaikyo died under twenty'; therefore, her early death seems to have been widely known during the medieval period.
『正徹物語』にも「宮内卿は廿よりうちになくなりにしかば」とあって、彼女が夭折したことは、中世期にひろく知られていた事実らしい。