Washington Adoption — Petition is a legal document that is filed in the Superior Court of Washington State to begin the adoption process. It is used when a person or couple wishes to adopt a child in the state of Washington. The petition must include an accurate and detailed description of the adoptive parents, the child, the reasons for the adoption, and the special circumstances of the adoption. Depending on the individual circumstances, the petition may also include a statement of financial responsibility, a statement of health, and other information. There are two types of Washington Adoption — Petitions: stepparent adoption and adult adoption. A stepparent adoption is when a stepparent wishes to legally adopt a child who is already their stepchild. An adult adoption is when an adult wishes to be adopted by another adult.