An 8-year-old girl in Georgia was reportedly killed on Thursday when a car struck her as she tried to get on a school bus.

Kaylee Andre, 25, allegedly mowed down Adalynn Pierce in Henry County after she passed a school bus with its stop sign out. WSB-TV reported that Pierce was trying to get on the school bus at the time of the deadly crash.

According to WXIA, Pierce’s mother witnessed her daughter crossing a two-lane street and being struck right before she got on the bus.

“When the accident happened, she [Andre] stayed by my side the whole time. She’s the one who called 911 for me, and she just kept screaming how sorry she was,” Pierce’s mother said.  “Law enforcement has said she has been nothing but cooperative the whole time. It was a mistake. Anyone could have made the same mistake.”

Andre is charged with homicide by vehicle, failure to stop for a school bus loading and unloading, and failure to exercise due care. Her bail was set at $20,000, according to WSB.