Tex. Fam. Code § 6.201 : FAMILY CODE — THE MARRIAGE RELATIONSHIP — DISSOLUTION OF MARRIAGE — SUIT FOR DISSOLUTION OF MARRIAGE — DECLARING A MARRIAGE VOID — Consanguinity TEXT PDF A marriage is void if one party to the marriage is related to the other as: (1) an ancestor or descendant, by blood or adoption; (2) a brother or sister, of the whole or half blood or by adoption; (3) a parent's brother or sister, of the whole or half blood or by adoption; or (4) a son or daughter of a brother or sister, of the whole or half blood or by adoption. Tex. Fam. Code § 6.201 Added by Acts 1997, 75th Leg., ch. 7, Sec. 1, eff. 4/17/1997.