According to "Shijuhachikan den" (Emperor's document), when he was 9 years old, he lost his father due to an attack at night by a warrior Sada-akira of Minamoto clan, but because of his father's final words he gave up his desire for a revenge.
『四十八巻伝』（勅伝）などによれば、9歳のとき、源内武者貞明の夜討によって父を失うが、その際の父の遺言によってあだ討ちを断念する。