Dijanelle Fowler, 25, also faces charges of child cruelty and concealing the June 15 death of Skylar Fowler, WSB reports.
Fowler surrendered Monday night, after investigators spent weeks searching for her.
"She's going to have to live with that for the rest of her life - that her child died in a car," said Moneisha Jones, a shopper.
"They shouldn't leave kids in the car at all - winter, spring, summer or fall - because it's dangerous," said Tony Brinson, another shopper.
Arrest warrants state Fowler left the air conditioner in the car running during a six-hour hair appointment at a salon in the Tucker area. When she returned, the car had shut off and her child was dead.
But instead of calling 911, DeKalb County Police Captain J.A. Lewis said, "She received a jump or a boost before leaving the hair salon."
Warrants reveal the man who helped her was unlikely to see the child's body in the backseat, because there were "lots of clothes" to cover her. Fowler left after her car got a jump.
Lewis said investigators believe Fowler rode around with her dead child for hours. Court documents also say Fowler sent a text to the child's godfather, saying she was headed to urgent care for a headache.
Documents show she Googled "seizure symptoms" before parking at a Emory hospital deck later that afternoon, where she finally called 911 saying she was having a seizure. Fowler was hospitalized and released.
DeKalb County police said the baby was found dead inside the car in the parking deck.
It wasn't immediately clear whether Fowler has a lawyer.
The Associated Press contributed to this report.
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