TEX. PROB. CODE ANN. § 149C(a) states the court may remove an independent executor when:
(1) the independent executor fails to return within ninety days after qualification, unless such time is extended by order of the court, an inventory of the property of the estate and list of claims that have come to the independent executor's knowledge;
(2) sufficient grounds appear to support belief that the independent executor has misapplied or embezzled, or that the independent executor is about to misapply or embezzle, all or any part of the property committed to the independent executor's care;
(3) the independent executor fails to make an accounting which is required by law to be made;
(4) the independent executor fails to timely file the affidavit or certificate required by Section 128A of this code;
(5) the independent executor is proved to have been guilty of gross misconduct or gross mismanagement in the performance of the independent executor's duties; or
(6) the independent executor becomes an incapacitated person, or is sentenced to the penitentiary, or from any other cause becomes legally incapacitated from properly performing the independent executor's fiduciary duties.
In Kappus v. Kappus, 284 S.W.3d 831, 835 (Tex. 2009), the Supreme Court stated that "the grounds to remove an independent executor post-appointment are different from those to disqualify an executor pre-appointment." 284 S.W.3d at 835.
The Court noted that "section 149C lists six specific grounds for removal, none quite as expansive as unsuitability." Id.