[3] On February 13, 1854, then sixteen-year-old Anna was married to the 34-year-old Stephen Vanderburgh Harkness, an early investor with John D. Rockefeller who became the second-largest shareholder in Standard Oil before his death in March 1888.
[2] Stephen had previously been married to Laura Osborne, who died in August 1852, and with whom he had three children, only one of whom, Lamon V. Harkness, was living at the time of their marriage.
[13][18] On July 29, 1895, within a year of Florence's marriage to Louis Severance, the former Treasurer of Standard Oil, their second daughter also died.
Similarly, Anna and her son-in-law Louis donated the funds for the construction of the Florence Harkness Memorial Chapel at Case Western Reserve University in Cleveland.
Anna's portrait by Albert Herter is displayed in the dining hall of Saybrook College, part of the Memorial Quadrangle.