Texas Estates Code - EST § 254.002. Bequests to Certain Subscribing Witnesses

(a) Except as provided by Subsection (c), if a devisee under a will is also a subscribing witness to the will and the will cannot be otherwise established:

(b) Notwithstanding Subsection (a), if the subscribing witness described by that subsection would have been entitled to a share of the testator's estate had the testator died intestate, the witness is entitled to as much of that share as does not exceed the value of the bequest to the witness under the will.

(c) If the testimony of a subscribing witness described by Subsection (a) proving the will is corroborated by at least one disinterested and credible person who testifies that the subscribing witness's testimony is true and correct: