The story of John Farrar (1779–1853) and Eliza Ware Rotch (1791–1870) is neither a tale about a female mathematician nor one of the “making” of a mathematical career. Rather, the productivity of John, who is known to historians of American mathematics for the Harvard College series of mathematics and natural philosophy textbooks that bears his name, had already begun to decline by the time he married Eliza in 1828. She then embarked on her own career of adapting novels and biographies for children and writing self-improvement manuals. Despite their joint efforts to continue writing and to preserve their social and professional connections, the activities of both John and Eliza were effectively brought to an end by the decades John spent fully incapacitated by illness. An exploration of how their marriage was interwoven with their careers adds details to their biographies and suggests connections to the historical analysis of dual-career marriages and to examinations of how such unions can be impacted by the poor health of one or both partners.