In a tragic accident late last week, Nashville Mayor Karl Dean's 2-year-old niece died after accidentally being back over by a vehicle driven by her father. The girl apparently had moved behind the vehicle while on her scooter as the man was backing out of the driveway. She was taken to. St. Thomas Hospital and then transferred to Vanderbilt, where she died, according to The Tennessean.

Such tragic driveway car accidents are not exactly common, but they are certainly not unheard of. Between 1990 and 2010, there were 14 fatalities in which children were accidentally backed over in Tennessee. Every week in the U.S., about 50 children are injured in this type of accident. On average about two of them die, according to News Channel 5.

One emergency room doctor at Centennial Medical Center says there are steps parents can take to prevent accidents of this nature. One important thing, she says, is understanding that extremely young children don't necessarily have a sense of safety.

Another step parents can take: If a parent is going to be backing out the driveway and knows a child is playing outside, it's best to make sure another parent or adult is with the child or at least watching where they are.

Unfortunately, very small children are very difficult to see behind or in front of a vehicle. Even in low-impact collisions, children's injuries can be serious because their bones are still developing.

When in doubt, it's best to be extra cautious.

Source: News Channel 5, "Doctors offer tips to prevent driveway accidents," Marcus Washington, Feb. 17, 2012