Yes in Texas, it is legal for a minor to drink alcohol in the presence of their parent, guardian, or adult spouse. Texas is one of the few states that permits alcohol consumption by people under 21 if a parent or legal guardian is physically present at the time of drinking. This rule applies at restaurants, private homes, weddings, and other social gatherings.
Must not be Texan:
https://www.legaltexastx.com/is-it-legal-to-drink-with-your-parents-in-texas/