Can an Adopted Child Inherit From Her Birth Parents?
Adopted children have two sets of parents: their biological (birth) parents, and their adoptive parents.  Under Washington intestate succession law, adoptive children do not automatically receive property from their birth parent(s).  Instead, the child is considered a child of the adoptive parents and inherits from them.  Of course this only applies when there is no will.  If you gave a child up for adoption and want to ensure that the child receives part of your estate, you must accomplish this through a will or other estate planning document.