Mariah Dachtler was reported to have run away from home on June 26, 2018 sometime during the afternoon. She is white, 5'3" to 5'4", and 110 pounds. She has a thin build, long dark hair, and brown eyes. NamUs #MP52300 - The National Missing and Unidentified Persons System (NamUs) Kelso police seeking information on juvenile runaway Cowlitz County News
Possible UID match mentioned by @coffeeandacig: WA - WA - Thurston Co, WhtFem UP57709, 13-19, found in wooded area, May'19
Her NAMUS page is still up. I found 2 FB pages for Mariah: https://www.facebook.com/ryry.farnsdac "Mariah Marie Farnsworth Dachtler" Last public post was in June 2016. https://www.facebook.com/mariah.farnsworth.7 "Mariah Dachtler" Last public post was in July 2014.
My Dad lives in Kelso now and there's not been any updates in the news on her for a year. She could have headed down to Portland - there's a pretty large homeless youth population down there OR up to Seattle (for whatever reason, most of the kids I grew up with that left SW Washington after graduation went to Seattle).