Suppose that in their infinite pubescent wisdom, a 12-year-old girl and a 13-year-old boy decided that they wanted to get married, somehow acquired a kosher ring and witnesses, performed kiddushin, and then refused to give or receive a get.
Could their parents and/or school principal get the marriage invalidated without their cooperation? If not, would they have any obligations to each other? How should such a couple conduct themselves?
(As always, CYLOR.)