This paper aims to examine how parents use the argument from authority and its effectiveness to persuade their children to accept rules and prescriptions during mealtimes. Using the model of a critical discussion integrated with the Argumentum Model of Topics as analytical approach, a corpus of 31 arguments from authority advanced by parents were analyzed. The results of this study show that parents always refer to an adult as source of authority. This is mostly themselves (self-oriented argument), and, less frequently, a third party (other-oriented argument) such as a grandparent or a child’s teacher. In light of these results, it is reasonable to assume that for the parents the reference to themselves is a more effective argument than the reference to a third party. However, in the corpus the children are more prone to accept their parents’ argumentation when the authority is another adult and not one of their parents.