So as much as I would hate to hear someone else saying this to my parents, I would say just talk to him and come up with a compromise on this.There is no way I'd let my 13yr old date a 17yr old.And the other way around, I wouldn't let my 17 yr old date a 13 yr old.I don't care how much "maturity" kids have these days , kids are being forced to grow up too fast as it is.Even if he is a really good guy, that doesn't mean he will never break her heart.Me and my dad don't really get along either, so I can completely relate.I have a very Mature 13 (almost 14) yr old daughter.. She came home & told me she really liked this boy & He liked her @ 1st her father & I was like NO way will that ever happen & then after having a long talk with her & inviting him over for dinner we found out he was a very good kid with Manners, Morals & good values..
She & I are very close & talk about everything, My husband & her on the other hand can't set in the same room without fighting & Yes it is His fault...I do think that 13 is too young to date, but you have already allowed it.I would say that a parent has to be with them until she is 15/16 and would not allow the boy to drive her. Like a bunch of girls and a bunch of guys all go roller skating together and a pizza afterwards. No offense intended, and everyone is entitled to raise their own children as they see fit.We look down on pedophiles but then we let our little girls date much older guys and dress them in clothes that say " juicy" on the butt.
I personally would never allow this of my own children.And the best relationships always come from strong friendships.