As my thread in this forum and my above reply point out, there are many reasons why adults, even older youth, should not be spending one-on-one time with a younger child. One reason is, it minimizes the opportunity for anyone to be taken advantage of. Another is, it helps identify people unwilling to play by the rules. Another, it provides accountability and ensures that the program remains free of accusations or realities of misconduct.
No one is talking about denying friendship, only the context in which it should happen when one person is older than the other, and in a position of authority. That context should be in a group setting, or in a public enough place (like a mall) where there are many people around that it is not one-on-one.
With respect, sense is making sure no incidents involving children or accusations of such happen, and the surest way to do that is to have boundaries around programs that work with children. I fail to see why that is a bad thing, or why it is "legalism."
Well first of all, the OP hasn't been back to this thread in a good long while, so this seems completely pointless. With respect, just about the only thing that separates a 16 & an 18 year old, is the legal definition of adult. So yes, all the fuss around here, it's pure legalism. Nothing more than that.
Now if you wanted to have boundaries between teens & actual children, like little kids, not just teens who legally aren't adults, that's totally fine. But boundaries between 2 teen girls being pals? Gracious. Get a grip.
FWIW - I'm 18, had been a youth leader at my church till a week ago, when I had to bow out due to not having the time with a job I just started, on top of being a full time student in engineering. Was also ROTC leader in HS, with kids who were older & younger. I go to a 4 year college, but I'd say about 80% of the YM at our church go to the community college. Some start college at age 18 or 19, lots start at 16 or even 15 to do dual enrollment. Kids who play sports, do ROTC, what have you, stay in HS all 4 years. Most of the rest go ahead & start CC on account of the big cost savings you get. It's pretty common for there to be a 16 year old who is 2 grades ahead of the 18 year old. Also real common for somebody who is older to look & act younger, some of the guys are still growing at 18, 19, 20. The girls are finished with all that by then. At our church, all the teens are part of youth. We've got JR youth for the MS group, and SR youth that goes to 20. Everybody's friends with each other. We just don't go around carding each other when we make our pals. We don't stop & say hey, you under or over 18 when we give rides, get lunch, go fishing, what have you. We just don't do legalism like that. Now, guys & gals are urged to use a lot of discernment about being 1 on 1 together, but the OP is a gal talking about friendship with another gal. We have no problem at all with that sort of thing, encourage it in fact. I did talk this over 1 day with our pastor out of interest. He just could not believe the fuss folks made on here, but it's the internet. I hope the girl who made this OP just talked it out with her pastor, realized there was no sensible reason for a fuss & is now friends with that girl who wants to be friends with her.