Lisa Marie Morris, of the 2400 block of Patrick Avenue, has been charged with second degree cruelty to children, sheriff's Sgt. Ken Rogers said.
Investigator Thelma Gilchrist said the child was taken to Medical College of Georgia Hospital in critical condition.
Investigator Gilchrist said the baby was left in Ms. Morris' vehicle from about 11:30 a.m. and 12:30 p.m. outside Ms. Morris' home. She said the mother apparently forgot the child inside the car, which had its windows rolled up.
If the child were to die, charges would be upgraded to felony murder, Sgt. Rogers said. A page to a MCG spokesperson seeking an update on the child's condition wasn't immediately returned Thursday night.