Empress Genmei
Emperor Monmu ruled until his death in 707, at which point he was succeeded by his mother, Empress Genmei, who was also his first cousin once removed and his first cousin twice removed. He left a young son by Fujiwara no Miyako, a daughter of Fujiwara no Fuhito: Obito no miko (Prince Obito), who eventually became Emperor Shōmu.