In 923, Morosuke received his first appointment to a post at age 16; in the following year, Moriko gave birth to the eldest son and heir FUJIWARA no Koretada.
師輔が延長(元号)元年（923年）に16歳で初めて叙任を受け、翌年に早くも盛子が嫡男藤原伊尹を生んでいる。