Section 11.603 - Invalid or prohibited marriages(a) The following marriages are prohibited:(1) A marriage entered into prior to the dissolution of an earlier marriage of one of the parties;(2) A marriage between an ancestor and a descendant, or between a brother and a sister, whether the relationship is by the half or the whole blood;(3) A marriage between an aunt and a nephew or between an uncle and a niece, whether the relationship is by the half or the whole blood, except as to marriages permitted by established tribal custom;(4) A marriage prohibited by custom and usage of the tribe.(b) Children born of a prohibited marriage are legitimate.