Ejigayheu H. Tsegaye, had been taken into custody earlier and released, but charges against her are pending, Robertson said.
Tsegaye, who was northbound on Rays Road, had a green light, Robertson said, but the school bus was stopped with its lights flashing and stop sign out. The mother and child were in a crosswalk when they were struck.
Investigators will determine how fast the woman was going when the accident occurred. Tsegaye had two children in her car at the time.
Robertson said the school bus had children on board. The bus was headed to the International Community Charter School in Decatur.
A mother and an 8-year-old girl were struck by a car Friday in DeKalb County.
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