Princess of stories

Samir is a little boy who always loved listening to stories. His father used to tell him stories, and one night Samir said to his father: "Dad, I want to hear a story!" So his father began to tell: "Once upon a time, there was a couple who had seven children, and the youngest of them was as small as a thumb." Why does Samir interrupt his father during the story? Why does he ask so many questions? ...