I recollect seeing a movie that started with a family going on vacation in the outback and parking too close to a cliff that they subsequently went over, leaving the child or children to fend for himself in the outback. Any help out there... or do I need to dial back my meds

The only similar film I can think of is that of 'Walkabout'

http://en.wikipedia.org/wiki/Walkabout_(film)

Hope that helps?

The Earthling (http://www.imdb.com/title/tt0080671/).