A Pennsylvania Petition For Modification of An Existing Support Order is a legal document that must be filed in order to change or modify an existing child support, spousal support, or medical support order. This petition can be filed by either the paying parent or the receiving parent in the existing support order. There are two types of modification petitions: a Petition to Modify an Order of Support (DC-15) and a Petition to Modify an Order or Agreement (DC-16). The DC-15 petition is used for modification of an existing child support or spousal support order, while the DC-16 petition is used to modify an existing medical support order. Both petitions require the petitioner to provide detailed information regarding the current order and the reasons why the order should be modified. Additionally, the petitioner must provide proof of income and other financial information to support their request for the modification.