During his lifetime, Jefferson claimed ownership of over 600 slaves, who were kept in his household and on his plantations. Since Jefferson's time, controversy has revolved around his relationship with Sally Hemings, a mixed-race enslaved woman and his late wife's half-sister. According to DNA evidence from surviving descendants and oral history Jefferson probably fathered at least six children with Hemings, including four that survived to adulthood. Evidence suggests that Jefferson started the relationship with Hemings when they were in Paris, where she arrived at the age of 14, when Jefferson was 44. By the time she returned to the United States at 16, she was pregnant.