The obligation of the father as hereby provided creates also a cause of action on behalf of the legal representative of the mother, or on behalf of third persons furnishing support or defraying the reasonable expenses thereof, where paternity has been judicially established by proceedings brought by the mother or by or on behalf of the child or by the authorities charged with its support, or where paternity has been acknowledged by the father in writing or by the part performance of the obligations imposed upon him.
Iowa Code § 600B.4