CA Prob Code Section 6450

Subject to the provisions of this chapter, a relationship of parent and child exists for the purpose of determining intestate succession by, through, or from a person in the following circumstances:

(a)

The relationship of parent and child exists between a person and the person’s natural parents, regardless of the marital status of the natural parents.

(b)

The relationship of parent and child exists between an adopted person and the person’s adopting parent or parents.