Yeah, I remember in hs when a bunch of guys in my school who were older than ME were into my younger sister....I was mortified. I was like, she's fresh out of elementary school, and you guys are about to graduate...wtf! It seemed really wrong even back THEN. There is a HUGE difference. Funny thing was, none of the older girls in school would date them because they were wise enough to know better. I agree w/Abercrom....the difference b/w 13 and 18 is much bigger than b/w say, 20 and 30.