The Attorney General shall enter into an agreement with the Secretary of Health and Human Services, as authorized by 42 U.S.C. § 663, under which the services of the Parent Locator Service established pursuant to 42 U.S.C. § 653 are made available to determine the whereabouts of any absent parent or child in order to enforce a law with respect to the unlawful taking or restraint of a child or to make or enforce a determination of the custody of a child.