Court Forms: Petition to Modify Child Support. If you have an open case with the Division of Child Support, you can ask DCS to review your order for changes (called a modification).Use this to change a final child support order you got, for example, when you finalized your divorce or parentage case. We explain here how to choose one. To change a child support order in Washington State, there are two different ways to proceed. Self-explanatory templates are available on the Washington Court Forms Website under Family Law > Child Support > Petition to Modify Child Support. Learn the rules in Washington State for changing the amount of child support you're paying or receiving—and how to get help with a modification request. Download Washington Child Support Modification template, modify and send for signing using BoloForms Signature. For additional help with select forms, visit Washington Law Help for a series of interactive interviews that will create completed forms for you to use. If you are unable to find an attorney for your case, online resources may be available to assist you in filling out the forms.