Seventeen-year-old Bryanna Hamilton is now charged with two counts of felony death by motor vehicle and two counts of felony assault by motor vehicle.
She turned herself in to police Friday afternoon.
Hamilton was charged earlier this week with driving under the influence, speeding, careless and wreckless driving and driving without an operator's license in the August 6 crash on Rosehill Road.
Investigators say Hamilton was driving when she lost control of the SUV and crashed.
"She is really going through a lot," said Hamilton's Aunt, Krystal Hamilton. "The whole family is. Our heart goes out to those kids and their parents, not just the two that passed -- all of the kids that were in the car."
Denzel Graves, 16, died at the scene, while Cheyenna Cummings, 18, died Sunday at the hospital as a result of her injuries.
"We have two deaths here, so it's pretty serious," said Eric Dow, Fayetteville Police Department. "Anytime that you have alcohol with death, you're automatically looking at manslaughter and felony type charges."
Also in the car were Alya Shaw, 19, Chyna Harris, 18, Benyetta Nicholas, 17, and Isaiah Nicholas, 14. They all suffered non-life-threatening injuries.
"Those were her friends," Krystal said. "It's been hard on us trying to keep her on top of water because it like she keeps saying she's sorry. She won't look at herself in the mirror or anything. You know, and it was an accident."
Krystal says she doesn't blame her niece. "By them drinking, I don't blame her. I blame whoever sold them the alcohol because if they would never gave it to her, she wouldn't have been able to drink and drive."
"I didn't have anything to do with it," parent Tierra Washington said. "I just allowed ya'll to have a party at my house."
Washington, 22, admits the teens were having a party at her house but accepts no responsibility for the drunken teens or the crash.
"As far as alcohol wise, I didn't give you alcohol," she explained. "If you decided to come to my house and you were drinking and then you decided to, under your own discretion, get in a car with somebody that was also drinking and driving -- that was your choice."
Alcohol control officers disagree. ABC11 has learned that Washington will be charged Monday for her role in the incident. The owner of the convenience store on Ramsey Street who sold the alcohol to the teens without checking their ID also will be charged.