Minamoto Rinshi (964-1053) was Michinaga's principal wife and mother of six attractive and intelligent children—two sons and four daughters, three of whom became empresses. It was due to these beautiful daughters and the imperial children they bore that Michinaga was able to secure his powerful position as regent. Rinshi is a prime example of the importance of marital connections to a man's career in the Heian era. The preferred form of residence after marriage was for the man to live at his wife's house. Sons were expected to succeed by making careers at court, while daughters inherited the family property. Rinshi owned the beautiful Tsuchimikado Mansion where her daughter Empress Shōshi returned from the palace to bear her children. The opening section of Murasaki's Diary describes the scene there just before and during the birth of the prince. Rinshi is described in the historical Tale of Flowering Fortunes as "small and attractively plump with richly shining hair." There is even an incident in which Michinaga is depicted gazing adoringly at his wife: "Look at her!" He said to the nurse holding baby Kishi. "What do you think of the mother of these children? She looks as young as her daughters! And her hair!"

‍   Nevertheless, Rinshi had a jealous side, as can be seen in several places in Murasaki's Diary. While the empress and her attendants were staying at the Tsuchimikado, Rinshi sent Murasaki a great wad of fabric damp with chrysanthemum dew for the purpose of "wiping away old age once and for all"—implying that it would take a lot to erase Murasaki's wrinkles. Murasaki's response was a poem sending the barb straight back to Rinshi—although she had more sense than to actually send it. Later, when Murasaki had taken a leave of absence, Rinshi sent her a note implying that she was staying away out of spite. 

‍   Another scene from the Diary describes the boozy carousing during one of the many celebrations following the birth of Prince Atsuhira. Here, Michinaga drunkenly boasts his poetic prowess, and Rinshi rather disgustedly gets up and leaves the room. My sense of her is a lady with a temper that she felt little compunction to smother.