Cabot also published seven books on ethics and childhood education between 1906 and 1929, a privately printed three-volume biography of her parents, and many articles and pamphlets.

On October 26, 1894,[2] she married Dr. Richard Clarke Cabot (1868–1939), physician and professor of medicine and social ethics at Harvard.

They also spent time in Cohasset, Massachusetts, and at the Cabot family house in North East Harbor, Maine, and camped on Spruce Island, Saranac, New York, during many summers.

Their lifelong correspondence, from the beginning of their courtship in 1888 through the year of Cabot's death, documents her ambivalent feelings about leaving her own family to accept Richard's proposal of marriage, and their initial disagreement about having children.

This portion of Series III also contains letters, some to both Cabot and Richard, from a wide variety of friends and acquaintances; some are personal, and others are about charitable donations, lecture invitations, and board meetings.