Financial Disclosure Form​​ This form is required if you are asking to change any financial orders, such as child support. A modification of a child support order may be requested if there has been a substantial change of circumstances since the order was entered.Obtain the Necessary Forms: Contact your local family court or child support agency to obtain the required forms for requesting a modification of child support. A child support order may be reviewed at any time on the basis of changed circumstances. What forms do I use to modify a motion for child support in Clark County, Las Vegas, Nevada? I dont seem to find it in the self help catalog online. Fill out the following forms. B. Notarize the Motion to Modify – The Motion to Modify must be signed in front of a notary. Under Nevada law, parents can request a child support review every three years. A 20 percent change in income or change in custody is not required.