Very sad Neil, sounds like she may have seen the door flapping in the rear view mirror from the passenger seat and walked back to try to close it. I wasn't too sure where Hine Hill was so took the liberty to google it; http://en.wikipedia.org/wiki/Hines_Hill,_Western_Australia (240kms east of Perth).
OMG, how tragic, I must admit I had something similar, realised that my door wasnt closed properly, tried to open it while i was driving but it was toooo heavy for me, so i stopped to slam it shut., I can see how this would've happened.
My sympathy to her family.
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