This microhistory analyzes the efforts of a widowed mother, Teresa Boncompagni, to maintain custody of her only daughter, Cornelia. Teresa protested her brother-in-law's legal right to Cornelia's custody. The mother's resistance combined a savvy understanding of the Roman judicial system with an insistence upon the centrality of motherly affection and maternal daily care to the child's well-being. She argued that the concept of free will necessitated a period of childhood exempt from family pressure to marry the man her brother-in-law had chosen. Although Teresa's adversaries pronounced her views outrageous, and maternal affection and advocacy would later be sanitized to include affection but to exclude women's resistance, Teresa's efforts succeeded in convincing even her enemies that a good mother knew how to fight legally and that the emotional bond epitomized by affective mothering was paramount to the healthy development of the child.