ed in 8 CFR 208.30(e)(6)(iii)(B), (C) and (D) only, ???legal guardian??? means a person currently vested with legal custody of such an alien or vested with legal authority to act on the alien's behalf, provided that such an alien is both unmarried and less than 18 years of age, and provided further that any dispute with respect to whether an individual is a legal guardian will be resolved on the b