An obligor-parent alleged to be in arrears may use any of the following grounds as a defense to the motion filed pursuant to this article or as a basis for filing a motion to stop a sale or use of assets under Section 4631:

1. (a) Child support payments are not in arrears.
2. (b) Laches.
3. (c) There has been a change in the custody of the children.
4. (d) There is a pending motion for reduction in support due to a reduction in income.
5. (e) Illness or disability.
6. (f) Unemployment.
7. (g) Serious adverse impact on the immediate family of the obligor-parent residing with the obligor-parent that outweighs the impact of denial of the motion or stopping the sale on obligee.
8. (h) Serious impairment of the ability of the obligor-parent to generate income.
9. (i) Other emergency conditions.