I am the stepmom of an 18-yr-old senior girl, as well as mom of two girls (college soph. & h.s. jr.). The stepdaughter ran away 2 weeks ago after we grounded her for a day for having her 20-yr-old boyfriend at her grandma's house. This rule was put into place following an incident when she was 16. Our rule was no dating for anyone until their jr. year, but her grandma was allowing a 19-yr-old to come pick her up for dates. Well, one night grandma wasn't home and things almost went too far.