Texas Estates Code - EST § 32.002. Original Jurisdiction for Probate Proceedings

(a) In a county in which there is no statutory probate court or county court at law exercising original probate jurisdiction, the county court has original jurisdiction of probate proceedings.

(b) In a county in which there is no statutory probate court, but in which there is a county court at law exercising original probate jurisdiction, the county court at law exercising original probate jurisdiction and the county court have concurrent original jurisdiction of probate proceedings, unless otherwise provided by law.  The judge of a county court may hear probate proceedings while sitting for the judge of any other county court.

(c) In a county in which there is a statutory probate court, the statutory probate court has original jurisdiction of probate proceedings.