(a) Except as provided by Subsection (a-1), a declaration under this subchapter must be signed by the declarant and be:
(1) written wholly in the declarant's handwriting; or
(2) attested to in the declarant's presence by at least two credible witnesses who are:
(A) 14 years of age or older; and
(B) not named as guardian or alternate guardian in the declaration.
(a-1) If the declaration does not expressly disqualify any individual from serving as guardian of the declarant's person or estate, the declaration must be signed by the declarant and may be acknowledged by a notary public instead of being attested to in the declarant's presence by witnesses as required by Subsection (a)(2).
(b) Notwithstanding Subsection (a) or (a-1), a declaration that is not written wholly in the declarant's handwriting may be signed by another person for the declarant under the direction of and in the presence of the declarant.
(c) A declaration described by Subsection (a)(2) may have attached a self-proving affidavit signed by the declarant and the witnesses attesting to:
(1) the competence of the declarant; and
(2) the execution of the declaration.