Nobita's grandmother, deceased before the story begins, passed away when Nobita was around three or in kindergarten. During his early childhood, she appeared as an elderly woman with gray hair in a bun, wearing traditional Japanese clothing. She possessed a gentle, nurturing personality defined by unconditional love and acceptance for her grandson, immediately recognizing and warmly welcoming an older Nobita during their time-travel reunion despite its unusual nature.

A teddy bear she repaired for Nobita in his early childhood serves as a significant personal item connecting them. Its rediscovery in the present ignites Nobita's emotional desire to see her again, driving the central time-travel narrative. Reuniting with Nobita approximately seven years before her death, she expresses heartfelt wishes to see him attend elementary school and to meet his future bride. Nobita fulfills the first wish by showing her his school backpack. Her second wish sets the main plot in motion as Nobita promises to grant it, demonstrating her enduring influence.

Her role expands significantly when Nobita and Doraemon bring her from the past to witness his future wedding ceremony, a unique event in the franchise allowing her to see a key milestone she did not live to experience. Observing the wedding speech, she privately notes Nobita's inherent strengths—particularly his determination and kindness—affirming these qualities as reasons Shizuka chose to marry him. Her presence fulfills her wish and completes her narrative arc.

Following the wedding, she returns to her original timeline. Nobita's subsequent use of the Forgetting Stick ensures no lasting memory alterations, preserving timeline stability and her canonical history. Her final narrative function reinforces the story's emotional core, affirming Nobita's positive traits and the enduring significance of familial bonds across time.