Family Code §2.006

(a) If an applicant who is 18 years of age or older is unable to appear personally before the county clerk to apply for a marriage license, any adult person or the other applicant may apply on behalf of the absent applicant. (b) The person applying on behalf of an absent applicant shall provide to the clerk: (1) notwithstanding Section 132.001 , Civil Practice and Remedies Code, the notarized affidavit of the absent applicant as provided by this subchapter; and (2) proof of the identity and age of the absent applicant under Section 2.005 (b). (c) Notwithstanding Subsection (a), the clerk may not issue a marriage license for which both applicants are absent unless the person applying on behalf of each absent applicant provides to the clerk an affidavit of the applicant declaring that the applicant is a member of the armed forces of the United States stationed in another country in support of combat or another military operation.