From Thomas Jefferson Encyclopedia
Elizabeth-Ann Fossett (Betsy-Ann) Isaacs (1812-1902) was the daughter of Joseph Fossett and Edith Hern. Joseph Fossett (1780-1858) was the son of Mary Hemings (1753-after 1834), the eldest daughter of Elizabeth "Betty" Hemings (1735-1807). He was foreman of the Monticello blacksmith shop and one of only five enslaved men freed by Jefferson in his will. His wife, Edith (1787-1854), learned French cookery at the President's House in Washington, D.C., and served as chief cook at Monticello during the period of Jefferson's retirement.
Fifteen-year-old Betsy-Ann Fossett, her mother, and seven siblings, were sold in the January 1827 dispersal sale following Jefferson's death. Her father, with the help of family members who were already free, was able to purchase and emancipate his wife and some of his eight children-including Betsy-Ann. The Fossetts moved Cincinnati, Ohio, about 1840.
Betsy-Ann Fossett, however, remained in Charlottesville, having married Tucker Isaacs, a free man of African-American and Jewish ancestry. When Isaacs fell under suspicion of forging "free papers" for escaped slaves in 1850, the family moved to Chillicothe, Ohio. They had nine children, one of whom was the mother of William Monroe Trotter (1872-1934), the crusading newspaper editor and noted civil rights leader.