In texas can a parent order an underage adult a drink at a restaurant?

I'm turning 20 in a matter of days and I've heard from other people my age that they've gone to restaurants before with their parent's and had them order alcoholic drinks for them. I asked my mother if she would buy me a drink for my birthday dinner and she had never heard of this Texas law where parents can give consent for their children to drink in restaurants under 21. I just wanted to make sure this was still perfectly legal so I can actually celebrate my birthday the way everyone else does, with a nice stiff drink haha.