The accident happened near Beechwood and Maroa around 8 p.m. Sunday.
Investigators say a 16-year-old girl was teaching her 15-year-old sister to drive. The older sister started pulling away from the curb to make a u-turn, when her younger sibling jumped on the back of the car. She then slid off and hit her head on the pavement.
The victim was taken to Community Regional Medical Center in critical condition.
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