Yevamos 96b - The Nine-Year-Old Yavam: The Oneg Yom Tov’s Revolutionary Chiddush

Can a nine-year-old boy actually perform yibum and acquire his deceased brother’s wife? According to Rashi, although a minor ordinarily cannot create a marriage, yibum may be different: since it does not require conscious intent, the boy’s act can create a real Torah-level acquisition.But that leads to a major problem. If he truly acquired the yevamah, why does the Mishnah treat the relationship as incomplete? And if he later grows up, marries a second woman, and dies, how can one brother perform chalitzah with the first woman while another still performs yibum with the second? Shouldn’t the rule of “לא יבנה” prohibit rebuilding the family once chalitzah has taken place?The Oneg Yom Tov answers with a revolutionary distinction: acquiring the yevamah and fulfilling the mitzvah of yibum are not necessarily the same thing. A nine-year-old may be capable of creating the marriage, while still being unable to accomplish the mitzvah’s deeper purpose of “הקמת שם”—perpetuating his deceased brother’s name.This episode explores the surprising halachic status of a nine-year-old yavam and the profound difference between creating a legal relationship, fulfilling a mitzvah, and completing the Torah’s ultimate purpose for that relationship.