Tex. Health & Safety Code § 713.010

This subchapter does not affect the right of a person who has an interest in a grave or burial lot, or who is related within the fifth degree by affinity or consanguinity, as determined under Chapter 573, Government Code, to, or is a direct descendant of, a decedent interred in the cemetery, to beautify or maintain a grave or burial lot individually or at the person's own expense in accordance with reasonable municipal rules.