She died just after 6 p.m. Tuesday at Duke Hospital, to which she had been flown by LifeFlight earlier in the day.
A friend came to Harris' mobile home about 1:30 p.m. Sunday and found her brutally beaten.
Harris' 18-month-old son was also in the home, but was not harmed. He is now with relatives.
Harris, 27, was divorced and lived about 8 miles north of Louisburg.
The sheriff's office say they have strong leads, and do not believe this was a case of random violence.