One reason is a child’s connection with their inner world is so easily lost that the younger child is still close to it, as it is not yet buried by opinions and judgements of the adult world. There is also the added benefit, that the young child’s presence among older kids cause them to explain in more detail what they are saying as they try to communicate it to them.
Yes, it is true their languages proficiency is often quite limited but DRAFT. their reveals of their inner perspectives is so real not just in their words but in the vibrance of their voices. in their voices is so precious and real. It paints reveals are so precious are they often give are
The Child's World: Zooms, Podcasts & Radio 