Mario D. Zuniga Jr., 17, was pronounced dead at Atlanta Medical Center at 12:22 p.m. Monday as a result of injuries he sustained in the Sunday crash, said Cobb County Police spokesman officer Joe Hernandez.
Barnes' eldest granddaughter, Lilly Salter, 6, was released from the hospital Sunday evening with cuts to her face, but her 4-year-old sister remained in the hospital Monday for surgery, a spokeswoman for the former governor said.
Ella Salter, 4, was to undergo surgery at Children's Healthcare of Atlanta at Scottish Rite Monday for a broken arm and shoulder, Anna Ruth Williams, Barnes' spokeswoman, told reporters outside the hospital Monday morning.
"She's going to have some pins placed in her arm and shoulder," Williams said.
Zuniga was driving a black 2002 Porsche Boxster south on Old Mountain Road near Marietta when he struck the front of the 2008 Honda Odyssey driven by Barnes' daughter, Allison Barnes Salter, around 12:40 p.m., Hernandez said.
Salter, of Marietta, was driving north on Old Mountain Road near Greymont Circle, police said. The Porsche crossed into her lane while attempting to negotiate a curve to the right, Hernandez said.
The posted speed limit is 30 mph, but investigators believe Zuniga was traveling faster.
Zuniga, of Kennesaw, had to be extricated from the vehicle before being transported to Atlanta Medical Center, Hernandez said. A 16-year-old passenger, whose name was not released, was transported to WellStar Kennestone Hospital for treatment of non-life-threatening injuries, he said.
Zuniga's father said Morning morning that his son suffered a serious head injury.
The elder Zuniga said the passenger was his son's friend and that the boy underwent surgery on his leg and was "doing fine."
Zuniga said his son was driving his own car and that the crash was "just an unfortunate accident."
"He was just a normal kid who had a bad accident," the father said.
Salter, 35, was taken to Kennestone and was released Sunday evening.
Williams said Salter was running errands at the time of the crash and that her youngest daughter was not in the vehicle. The two girls were in car seats and the airbags in the Honda deployed, Williams said, adding that police told the family that "lives would have been lost" had the kids been unrestrained.
Salter is an attorney in her father's Marietta law firm.
Williams, who spoke to reporters outside Scottish Rite, said Barnes had put his campaign on hold.
"Roy is focused on his family and therefore we have canceled all campaign events until further notice," Williams said.