Are they cheap to temporarily live in? Is it possible that the child would have lived rural temporarily because her parents needed a cheap place to live? Or flee some sort of mess they were in?
And if so. How would they have gone about finding a cheap place to stay? Internet, paper ? A real estate agent woud seem less likely or not?
Could they have been renting something and not been oficially registered doing so?
Quite often in smaller towns it is easy enough to ask around and get a rental by word of mouth. Although bonds are supposed to be paid before occupation and lodged to Residential Tenancies, some private landlords won't bother. So it is possible to rent something cheap and be off grid entirely with it.