Fam. Code, § 7611

A person is presumed to be the natural parent of a child if the person meets the conditions provided in Chapter 1 (commencing with Section 7540) or Chapter 3 (commencing with Section 7570) of Part 2 or in any of the following subdivisions:

(a) The presumed parent and the child’s natural mother are, or have been, married to each other and the child is born during the marriage, or within 300 days after the marriage is terminated by death, annulment, declaration of invalidity, or divorce, or after a judgment of separation is entered by a court.

(b) Before the child’s birth, the presumed parent and the child’s natural mother have attempted to marry each other by a marriage solemnized in apparent compliance with law, although the attempted marriage is or could be declared invalid, and either of the following is true:

(1) If the attempted marriage could be declared invalid only by a court, the child is born during the attempted marriage, or within 300 days after its termination by death, annulment, declaration of invalidity, or divorce.

(2) If the attempted marriage is invalid without a court order, the child is born within 300 days after the termination of cohabitation.

(c) After the child’s birth, the presumed parent and the child’s natural mother have married, or attempted to marry, each other by a marriage solemnized in apparent compliance with law, although the attempted marriage is or could be declared invalid, and either of the following is true:

(1) With the presumed parent’s consent, the presumed parent is named as the child’s parent on the child’s birth certificate.

(2) The presumed parent is obligated to support the child under a written voluntary promise or by court order.

(d) The presumed parent receives the child into their home and openly holds out the child as their natural child.

(e) The child is in utero after the death of the decedent and the conditions set forth in Section 249.5 of the Probate Code are satisfied.