One part of this post could be misinterpreted, and in fact, leaves out more of the grossness of the situation:
"It appears Thomas’s desires couldn’t be settled by Martha alone."
Sally Hemings was born around 1773. She was the daughter of John Wayles - an attorney, slave trader, and planter - and Betty Hemings, his slave.
Martha Wayles Skelton, Sally's half-sister, had been born in 1748, a good twenty five years earlier. Martha's second marriage was to Thomas Jefferson, her third cousin, in 1772. (This was not unusual at the time.) Martha and Thomas had six children. Four of these children didn't make it past the age of five.
In 1773, John Wayles died, and the Jeffersons inherited both his debts and his property - including more than 100 slaves. Betty Hemings and her ten children were among them. Betty's six youngest children were Martha's half siblings. Sally was probably an infant at this time.
In 1782, shortly after the birth of her last child, Martha died. On her deathbed, she made her husband promise never to marry again. Thomas Jefferson was in no way an early feminist - as Burr was - but he had been deeply devoted to his wife. (He basically moped around Monticello for three months after her death.)
In 1784, Jefferson was sent to replace Benjamin Franklin as Minister to France. He brought with him his daughter Patsy, who was eleven. His two youngest girls, Polly and Lucy, stayed at home with relatives. Lucy died of whooping cough in 1786, and Jefferson asked for Polly to be sent to France.
Jefferson requested that Abigail Adams (John Adams' wife) meet Polly when she arrived in London. The girl was supposed to be in charge of a nursemaid (Betty Hemings), but instead, Betty's 14 year old daughter, Sally, had been sent along to watch Polly. Sally was understandably totally out of her depth; Abigail Adams wrote that Sally "want[ed] more care than the child."
Sally acted as an attendant to Patsy and Polly while in France. The Jeffersons returned to Virginia in 1789. One of Sally's sons later wrote that his mother's first child died shortly after she returned from Paris, which means not only was Jefferson sleeping with his slave, he was sleeping with a sixteen-year old who grew up alongside his daughters.
Of Sally's six children, four lived to adulthood. A son and daughter both fled Monticello in their 20s and weren't followed - the daughter was supposedly given $50 and put in a carriage headed north. Jefferson only freed seven of his hundreds of slaves in total - two during his lifetime and five in his will. Two of the five men freed in his will were his sons. Thomas Jefferson did not free Sally.
