Nonna di Taeko, also referred to as Taeko's Grandmother, is a supporting character appearing in the 1966 flashback sequences of the film. She is the mother of Taeko's father and the paternal grandmother of Taeko and her two sisters, Nanako and Yaeko. At the time of the flashbacks she is around 67 years old and lives with the Okajima household in Tokyo.

Her personality is gentle, patient, and quietly observant. She rarely intervenes in the family's daily tensions but occasionally offers mild, wry commentary, such as remarking that all her children are selfish. Unlike Taeko's stern father and pragmatic mother, the grandmother provides a softer, more indulgent presence. She is the one who suggests a summer trip to Atami to satisfy young Taeko's wish to go somewhere, and she accompanies Taeko on that journey, creating a warm memory for the girl.

When the family tries an unripe pineapple, she is the one who finishes her portion without complaint and philosophically notes that living a long life brings many experiences. This reflects her resilience and her ability to find meaning in small moments. She also likes to reminisce about her late husband, keeping his memory alive for the grandchildren.

Her motivation appears to be simply supporting her family with kindness and stability. She does not drive any plot conflict, but her role is significant as a counterpoint to the more rigid family dynamics, offering Taeko a source of unconditional warmth and a link to a more forgiving, age-earned wisdom. There is no notable character development for her, as she remains a consistent, quietly nurturing figure throughout the flashbacks. Her notable ability is her capacity to offer simple, profound observations that comfort and guide Taeko, even in the midst of childhood frustrations.