The formal telling of the story of Passover is framed as a discussion with lots of questions and answers. The tradition that the youngest person asks the questions reflects the centrality of involving everyone in the seder. 

This night is different from all other nights of the year, but why? Before the story is read, the youngest child who can read asks the “Four questions”. (Identify the youngest reader and ask if they wish to read these.)

1. On all other nights, we eat all kinds of bread and crackers. Why do we eat only matzah on Passover?

2. On all other nights, we eat many kinds of vegetables and herbs. Why do we eat bitter herbs, at our Seder?”

3. On all other nights, we don’t usually dip one food into another. At our Seder, we dip the parsley (or celery) in salt water and the bitter herbs in charoses. Why do we dip foods twice tonight?

4. On all other nights, we eat sitting up straight. Why can we lean on a pillow tonight?”

haggadah Section: -- Four Questions
Source: Oranges & Olives Haggadah and The Wandering is Over Haggadah,