Teslin,

Another quick bit of info from Koester's data. Your article said she was 21, with a mental capacity of half that. Looking at Koester's data for 10-12 year olds he finds that in mountainous temperate terrain, about 25% are found within .8 km of the last known point, 50% within 1.6 km, 75% within 3.2 km miles, and 95% within 9.0 km.

"They may be hiding intentionally to avoid punishment, to gain attention, or sulking."

I hope you have success tomorrow!