If a minor (16) runs away from their house.......?

And their parents know they are a runaway, but they call the cops, would the cops file missing person AND runaway and put your photo in the newspaper, if the minor doesn't contact their parents at all? Also, would the cops discard the missing person/runaway file if the minor reaches 18 before they are caught? I want to have accurate information for the modern depiction of Bound for the North Star-True stories of fugitive slaves. The character who feels that she is a slave to her parents ran away and I need to know how the legal business would go down in real life