This was not an "unfortunate accident". Yes, it was.very unfortunate, but no accident in the real sense of the.word.
Number one, why would you strike up a conversation with someone and you have children to watch in a parking lot? Why would you not only assume a three year old got into an SUV unassisted, but then not even turn around and verify it? Did she not care if they had their seatbelts on either...hell the child should have been in a carseat at 3! Then, she takes the child back to her house after running over her?? What if she had died in her car? And who knows what kind of cockamamie story she'd have given at the hospital if someone hadn't flagged down the police.
This was so so wrong and preventable. That woman needs her a$$ kicked then thrown in jail.