I have an 80-year-old mother-in-law. She is currently healthy enough to enjoy home gardening, but the other day, she told me, “When I can no longer move, I’ll rely on you.” Besides my husband, who is the eldest son, she has two other daughters. All three live in the same city. When I discussed my mother-in-law’s request for care with my husband, he said, “You’re the eldest son’s wife,” implying it was natural for me to take care of her. Is it really my responsibility as “the eldest son’s wife”? (Female in her 60s, Sapporo)
■Obligation Falls on Direct Descendants, but Cooperation is Necessary
There is no rule stating that “the eldest son’s wife” must provide care. Regarding support obligations, the law (Civil Code, Article 877) states: “Direct lineal descendants and siblings have a mutual duty to support each other.”
Support means providing financial assistance to someone who cannot sustain themselves. In principle, the obligation falls on direct descendants—her children (your husband and his sisters).
There is no legal obligation for in-laws (such as daughters-in-law or sons-in-law) to provide support. However, spouses have a duty to cooperate with each other (Civil Code, Article 752). If your husband provides care, you are expected to assist.
