Questions represent a crucial tool of interaction between parents and children from a very early age. This study aims to investigate which function – argumentative or explanatory – most characterizes Why-questions asked by children to their parents in a natural setting such as mealtimes at home. Why-questions asked by 13 children – eight girls and five boys aged between three and seven years – coming from 10 middle- to upper-middle-class Swiss and Italian families with a high socio-cultural level were analyzed. (...) In the corpus, the explanatory function largely characterizes children’s Why-questions. Questions we observed play fundamentally an educational role, since they favor the acquisition of new information and the transmission from parents to children of parental behavioral models. The argumentative Why-questions, less frequently asked by children in our sample, are also important from an educational point of view. By these questions children challenge their parents to make clear the reasons behind their opinions, suggestions, rules and prescriptions, which are often largely implicit. Altogether, the results of this study indicate that both the explanatory and argumentative types of children’s Why-questions have a knowledge-seeking function, that is, children asking such questions are seeking knowledge of something. (shrink)