Who was the slave with whom Thomas Jefferson probably had several children?

Sarah "Sally" Hemings was an enslaved woman of mixed race owned by President Thomas Jefferson. It is believed that she and Jefferson had a long-term relationship and six children together, of whom four survived and all were given freedom by Thomas Jefferson.

To briefly describe Sally Hemings (1773-1835), she was a slave at Monticello; she lived in Paris with Jefferson and two of his daughters from 1787 to 1789; and she had at least six children. Hemings was the youngest of six siblings by the widowed planter John Wayles and his mixed race slave Betty Hemings.

In 1787, Hemings, at the age of 14, accompanied Jefferson's youngest daughter Mary (Polly) to London and then to Paris. At the time, Jefferson was serving as the U.S. Minister to France. Hemings spent two years there. It is believed by most historians that Jefferson began a sexual relationship with Hemings either in France or soon after their return to Monticello. Hemings had six children of record who were born into slavery; four survived to adulthood. Hemings was a domestic servant in Jefferson's house until his death.