Code of Federal Regulations Title 20. Employees' Benefits § 20.404.733 Evidence you are the legally adopting parent or legally adopted child

(a) A copy of the birth certificate made following the adoption;  or if this cannot be gotten, other evidence of the adoption;  and, if needed, evidence of the date of adoption;

(b) If the widow or widower adopted the child after the insured person died, the evidence described in paragraph (a) of this section;  your written statement whether the insured person was living in the same household with the child when he or she died (see § 404.760);  what support the child was getting from any other person or organization;  and if the widow or widower had a deemed valid marriage with the insured person, evidence of that marriage—see § 404.727;

(c) If you are the insured's stepchild, grandchild, or stepgrandchild as well as his or her adopted child, we may also ask you for evidence to show how you were related to the insured before the adoption.