Save a child

A warning for child car seat when a baby or small child is in the back something to remind the driver they are still in the car maybe something that attach to you when placing the child that connect to the driver to remind them it could save lots of baby and kids lives!
Michael L 07/25/2012
How would it know if a child is in the back though? Child seats weigh all kinds of different weights, and a newborn isn't even going to hardly register. How would it know the difference in an empty child seat and an occupied one?