After Robert Capato was diagnosed with cancer, he deposited sperm in a sperm bank because chemotherapy could cause sterility. Despite his treatment, Robert’s wife, Karen Capato (plaintiff), became pregnant naturally and gave birth to the couple’s son. Robert died in Florida soon afterward. Robert’s will, which was executed in Florida, named his son as a beneficiary. The Capatos had informed their attorney that they wanted any future children to be treated equitably with their son, but Robert’s will included no provisions regarding children conceived posthumously. After Robert’s death, Karen conceived and bore twins through in vitro fertilization using Robert’s sperm. Karen applied to the Social Security Administration (SSA) (defendant) for survivors-insurance benefits on the twins’ behalf. The SSA denied her claim on the ground that the Social Security Act (the Act), [42 U.S.C. § 301 et seq.], authorized benefits only if state intestacy law would allow the children to inherit from the decedent; [because Florida law disallowed posthumously conceived children from inheriting unless the decedent’s will provided for such children], the twins were barred from receiving SSA benefits. The United States District Court for the District of New Jersey affirmed. On appeal, the United States Court of Appeals for the Third Circuit interpreted the Act differently, concluding that state intestacy law was irrelevant if the children were biological and legitimate. Because the twins were the biological children of married parents, the Third Circuit reversed. The United States Supreme Court granted the SSA’s petition for certiorari.