The Christmas family were locals in Warrenton; there is still a Christmas family historical house standing (barely) in town. The Mordecais who stayed in the area mention the family's doings in their letters. One hair-raising report finds a drunken "T. Christmas" chasing his wife through the streets with a stick, breaking down doors and signs, even beating a man in his rage, because Betsy Christmas danced with another man at a party. (Caroline Mordecai Plunkett to Ellen Mordecai, 12 May 1826, Mordecai Family Papers, Southern Historical Collection; stay tuned, because Betsy Davis Christmas was a Mordecai alumna too--more on here in a few entries.) A later letter indicates that this man's problems continued: "Tom Christmas is out of jail, his mother & brother stood his securities." (Caroline Mordecai Plunkett to Ellen, 12 May 1828?, Jacob Mordecai Papers, Duke University)
Her sister Sarah Christmas married John H. Marshall in 1818. Sarah sometimes appears as Lucy D. Christmas in family histories, but with the nickname "Sally." The names Lucy and Lewis could be confusing on siblings, and maybe she preferred a more distinctive sound? She's "Sally D. Marshall" in a bit of 1820 paperwork about land. I can't find a record of children or a death date for either Sally or John Marshall; they may have left the area.