Have you shown her this one?
http://www.cpsafety.com/articles/StayRearFacing.aspx
The videos on it are rather poignant.
I believe ShyGeko came up with an analogy. I'll just copy from her.
"
Ok...think of it this way. Your child's spinal column and spinal cord are like a twizzler inside of a spiral phone cord. The bones in your child's neck do not even start to harden until they are a little over a year old. They don't get hard enough to withstand the forces of a crash until they are 2 or 3 years old. The forces exerted on your child's head in a crash while forward facing are calculated as the weight of their head (which most infants heads are around 5-8ish pounds) times the speed the car was traveling at impact. In other words, if you are traveling at 60mph when you hit a wall, your child’s head will fly forward and will temporarily be 480 pounds (if their head weighs 8 pounds)...480 pounds pulling on your child’s spinal column and spinal cord. Your child's spine can stretch about 2 inches, but his/her spinal cord can only stretch 1/4 of an inch before it experiences permanent, life threatening damage. This is where the twizzler and phone cord simliarity come into play. Pull on the phone cord while holding on to both ends of the twizzler. The cord will stretch but the twizzler will break...that is your child's spinal cord. The harness straps hold your child's body in place, but their head is still free to push forward. It has absolutely nothing to do with the muscles in their neck, or how strong they are. It has to do with the bones in their spine, and everyone’s spines mature at the same rate."
Pretty scary, huh? That's known as internal decapitation. They'll just look like they're sleeping in the back with their head slumped over.
Wendy
