Maybe the question is not "will they," but "when," as Marvel Comics seems to be crossing a fine line when it comes to teenage characters in their comic books.
Case in point is the following page from an issue of Wolverine and the X-Men #33 that a user on Reddit posted featuring a scantily clad 14-year-old girl.
There is also the fact that the new Nova, Sam Alexander, is a 15-year-old who is essentially a member of the cosmic Al-Queda.
Sam is forced to be a part of the Black Nova Corps (with a gun to his head to boot), which is equivalent of the Green Berets; so the message their sending is it's okay to send kids to war?
Think of any others?