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18 U.S. Code § 2261B - Enhanced penalty for stalkers of children

(a) In General.—
Except as provided in subsection (b), if the victim of an offense under section 2261A is under the age of 18 years, the maximum imprisonment for the offense is 5 years greater than the maximum term of imprisonment otherwise provided for that offense in section 2261.
(b) Limitation.—Subsection (a) shall not apply to a person who violates section 2261A if—
the person is subject to a sentence under section 2261(b)(5); and
the person is under the age of 18 at the time the offense occurred; or
the victim of the offense is not less than 15 nor more than 17 years of age and not more than 3 years younger than the person who committed the offense at the time the offense occurred.