Shiba Miya was the mother of Tatsuya and Miyuki and a member of the prestigious Yotsuba Family—specifically, the twin sister of Yotsuba Maya, the family's current head. She passed away before the events of the main series due to health complications, though fans do get to meet her through flashback sequences set in 2092, three years before the story's present day.
Content compiled by AnimeList.moe from publicly available sources.
