Texas Estates Code - EST § 202.004. Persons Who May Commence Proceeding to Declare Heirship

(1) the personal representative of the decedent's estate;

(2) a person claiming to be a creditor or the owner of all or part of the decedent's estate;

(3) if the decedent was a ward with respect to whom a guardian of the estate had been appointed, the guardian of the estate, provided that the proceeding is commenced and maintained in the probate court in which the proceedings for the guardianship of the estate were pending at the time of the decedent's death;

(4) a party seeking the appointment of an independent administrator under Section 401.003;  or

(5) the trustee of a trust holding assets for the benefit of a decedent.