There's a student in the rolls of the Mordecai school named Susan Cutler. She attended the school for two years, 1817-1818, and may be connected to a place called "Goodwynsville," and a person called Dr. Cutler. "We were rather surprised Friday," notes Caroline Mordecai in a February 1818 letter, "not at the arrival of Susan Cutler, but to see her accompanied by Lucinda Mason, they sleep in that share bed in the little room..." (Caroline to Ellen Mordecai, 2 February 1818, in the Jacob Mordecai Papers at Duke University) In another mention, we learn that Susan might have continued at the Warrenton school after the Mordecais sold it in 1818: "S. Cutler & H. Goodwyn return wh. their father--he was not alarmed but recd. such positive directions from Col. G. that he had no discretion." (Solomon to Rachel & Ellen, 11 April 1819, from Warrenton). Dr. Cutler appears in the school ledger in February 1817, making payments "for Susan, for M. Hill, for L. W. Mason." And again in June 1817, "for daughter, for L Mason." And again in November 1817, "for Miss Mason and daughter." Also in June 1818, again for Susan and Lucinda.
That's a good bit to work with! Okay, let's see what the online family histories can tell us...
Goodwynsville, no long inhabited, was in Dinwiddie County, Virginia, near Stony Creek.
A Dr. William Cutler (1766-1836) of "Mount Pleasant" in Dinwiddie County was a horse breeder of some repute, originally from Boston (some sources claim he was the son of Yale rector Rev. Dr. Timothy Cutler, but that seems unlikely as Timothy Cutler died in 1765, aged 81; perhaps they were kin, though). He married twice. His second wife (married 1804) was Susan (or Susanna) Greenway Mason (1764-1836), widow of William Mason. His son from his first marriage, John H. "Jack" Cutler, became a doctor, and was married to Lucinda
Wingfield Mason, youngest daughter of Susan Greenway Mason from her first
husband. Pretty sure this is the daughter we want: Susan Greenway Cutler, daughter of William and Susan. (So the Mordecai students Lucinda and Susan were half-sisters, and
became sisters-in-law as well.) She married twice: to Robert W. Mason (1801-1827) in 1826, and to Richard P. Stith (1801-1850) in 1837; she had a daughter, Susan Greenway Stith in 1840, just before she died in 1841. (Richard remarried, to Mary Louisa Parham.) There were four Mordecai students named Stith, so Susan Cutler's second husband may have been a longtime member of her wider social circle.