So my sister told me today that her and her boyfriend have been messing around. They re both super into waiting until marriage, and are both old enough to understand sex (she is 17 and he is 18). She also told me that she had a pregnancy scare because she is not on any form of birth control but denies having sex. They were messing around again and now she is sick. Should I be worried? Btw if you haven't figured it out yet, I'm very protextive over her.