20 CFR § 404.374 - Parent's relationship to the insured.
(c) You are the stepparent of the insured and you married the insured's parent or adoptive parent before the insured became 16 years old. The marriage must be valid under the laws of the State where the insured had his or her permanent home when he or she died. See § 404.303 for a definition of permanent home.
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