Traffic accident

My wife and her friend take a walk for an hour almost every day. I guess they start it for their health and for losing their weight. They usually do it from 6pm to 7pm, but recently it is already dark at 6pm. Two days ago, she(friend) had the great misfortune to be attacked by the car driven by young girl during taking a walk with my wife. Because of the darkness, the young girl couldn't see her walking. After all she had to stay in a hospital for some days.