Yoriko Sasaki, adoptive mother to Anna Sasaki, embraced parenthood with fervor after she and her husband welcomed the five-year-old orphan into their home. Determined to compensate for lost years, Yoriko poured affection into teaching Anna practical skills, though her inexperience led her to rely heavily on guidance from her older sister Setsu—often sulking when advice was delayed. Initially harmonious, their family dynamic fractured when Anna uncovered government subsidies supporting her adoption. Interpreting the financial aid as transactional, Anna retreated emotionally, addressing Yoriko as “aunt” rather than “mother.” Unaware of this revelation, Yoriko fretted over Anna’s withdrawal and worsening asthma, ultimately heeding a doctor’s counsel to send her to a seaside town under Setsu and Kiyomasa Ōiwa’s care. Throughout Anna’s summer away, Yoriko bridged the distance with letters and care packages. Their reunion brought a candid conversation: Yoriko clarified the subsidies’ irrelevance to their love, then shared a photograph of the marsh house unveiling Anna’s blood tie to Marnie, her late grandmother. This revelation dissolved Anna’s resentment, prompting her to finally call Yoriko “mother.” Yoriko’s devotion manifests in relentless focus on Anna’s well-being—evident in her strategic decisions and vulnerability under strain. Her bonds include a supportive yet distant husband, a reliance on Setsu’s wisdom, and a hard-won journey with Anna from fractured trust to heartfelt reconciliation.