Obtaining or enforcing child support

. (a) The agency shall undertake any legal or administrative action to secure support for a child by enforcing an existing court order or obtaining a court order of support. (b) To carry out its responsibilities imposed under this chapter, the agency, through the offices of the corporation counsel, the county attorneys, or the attorney general, may commence or appear in any proceeding before any court or administrative agency for the purpose of establishing paternity for children born out of wedlock or for the purpose of obtaining, enforcing, or modifying an order of support on behalf of any dependent or any other person for whom the agency has a duty to obtain or enforce an order for support under this chapter. The agency may commence or appear in any action on its own behalf, on behalf of any dependent child or custodial parent, or on behalf of any other person for whom the agency has a duty to obtain or enforce an order of support under this chapter. The agency shall obtain or enforce a child support order for the following children: (1) A child on whose behalf public assistance payments have been or are being made; (2) A child on whose behalf foster care payments have been or are being made under Title IV-E; or (3) Any other child, if a parent, guardian, or person having custody applies to the agency for assistance in obtaining or enforcing a child support order with respect to the child, regardless of whether public assistance payments have been made on the child's behalf.