Yasuko Kusakabe, mother of Satsuki and Mei, spends the story convalescing in a rural hospital due to a prolonged illness strongly hinted as tuberculosis. Her condition drives the family’s move to a countryside home near the medical facility, prioritizing fresh air and sunlight for her recovery. This absence reshapes their dynamics: her husband Tatsuo assumes primary caregiving duties, while Satsuki shoulders greater responsibility for Mei.

Physically distinguished by brown eyes and straight brown hair often tied in a low ponytail, Yasuko primarily wears a hospital gown, later transitioning to a blue kimono and dress upon returning home—a visual marker of her improving health. Her hospital interactions with her daughters reveal warmth and playfulness; she engages their tales of household spirits with humor, expressing curiosity to “meet the ghosts” to comfort them while masking her own vulnerability.

A striking resemblance to Satsuki surfaces during a tender moment of brushing her daughter’s hair, emphasizing their shared traits. Her marriage reflects mutual support, with Tatsuo steadfastly optimistic about her recovery. A pivotal narrative turn occurs when a minor cold postpones her home visit, inadvertently prompting Mei’s desperate attempt to deliver corn to the hospital alone—highlighting the children’s fragile emotional state.

The story concludes with her health restored enough to reunite with the family at home, depicted in closing scenes. Beyond the main narrative, she is referenced in *Mei and the Kittenbus* but remains offscreen. Her character draws inspiration from Hayao Miyazaki’s childhood experience of his mother’s tuberculosis hospitalization, grounding the narrative’s emotional core. Her documented role remains confined to these appearances.