Under California probate law, adopted children are treated no differently than biological children. So, for example, if a person dies without a will, his adopted and natural children are afforded the same status as heirs under California’s intestacy law. But that presumes the adopted children are, in fact, adopted in accordance with the law of California or another jurisdiction. What about children who are informally-i.e., not legally-adopted?
Many common law jurisdictions recognize “equitable adoption.” This means that if a person fulfills the role of a child, and the “parent” reciprocates, the courts may recognize a contractual relationship exists for the purposes of establishing intestate succession. As recognized by California courts, equitable adoption establishes the child’s right to receive property from the parent if he or she dies without a will.
It’s important to note that equitable adoption has no affect on estates where there is a valid will. Nor does it affect trusts. The only application of equitable adoption is to estates subject to intestacy law.