The following persons have a duty to maintain, financially, a child who is under the guardianship or in the custody of the Secretary under this Act or any other enactment:

(a) the child's parents;

(b) the child's guardians;

(c) the persons who were the child's guardians immediately before –

(i) the child was placed under the guardianship of the Secretary; or

(ii) the child was placed under the guardianship of a Government authority of another State under laws dealing with the care and protection of children, if the child was placed under the guardianship of the Secretary by notice filed with the Court under section 76 .