Mary Crossman is listed on page 162 in The History of Durham, ME.
As noted, Crossman, born 2 May 1777, married Isaac Clough. And note that Isaac was the son of Samuel Clough- History of Durham, Maine with Genealogical Notes.
Isaac, as the JCGS information shows, came from a very large family (11 siblings), and also produced a very large family (13 children).