Section 17(1)(a) of the Divorce Act provides that an application to vary, rescind or suspend a support order or any term thereof may be brought by either or both former spouses. A joint application is permissible under section 17(1)(a). The reference to "former spouse(s)" in section 17(1)(a) presupposes that an application to vary a permanent order for support cannot be instituted before the divorce judgment becomes effective pursuant to section 12 of the Divorce Act.17Section 17(1) confers no express authority on third parties to institute proceedings to vary, rescind or discharge spousal or child support orders, notwithstanding any assignment of such order made pursuant to section 20.1 of the Divorce Act.18A distinction is to be drawn between proceedings to enforce a support order and proceedings to vary the order.19
A child, in respect of whom support has been ordered, has no jurisdiction to apply to vary that order under section 17 of the Divorce Act, nor has the court any power to exercise a parens patriae jurisdiction on behalf of an adult child.20It has been held, however, that the words "former spouse" in section 17 of the Divorce Act include the personal representative of a deceased former spouse at least with respect to the variation of a child support order.21
It is well recognized that a court has a discretion not to entertain an application for variation by a payor spouse who is in continuous default.22There is no general principle that a person in arrears of support who has the capacity to pay should in every case be denied a hearing of his or her application to vary the support order.23
 See Chapter 11, Section B(17).
 See Robbins v. Robbins (1986), 43 Man. R. (2d) 53 (Q.B.); Pearson v. Pearson (1990), 25 R.F.L. (3d) 79 (N.B.Q.B.), wherein Logan J. held that the Minister of Income Assistance was not entitled to intervene and be added as a party on a divorced husband’s application to terminate spousal and child support merely because family members might become a public charge. In Galan v. Galan (1990), 25 R.F.L. (3d) 225 (Man. C.A.), however, the Director of Income Security was entitled to be heard on an application to reduce arrears of support where the wife had been largely supported through social assistance.
 See Section F, above in this chapter.
 Garbers v. Garbers (1993), 48 R.F.L. (3d) 217 (Ont. U.F.C.).
 Chalmers Estate v. Chalmers (1990), 29 R.F.L. (3d) 54 (Alta. Q.B.)...