What would be the effect of having a child narrate versus an adult to narrate?

For example, Angela's Ashes was narrated by a child so what would be altered if it was an adult instead looking back?

Child narrators question the things that we take for granted, and take for granted the things we question. When we look through their eyes, the way we see the world softens and shifts.

Because of this, child narrators in adult fiction are often used to explore family situations, or broader societal issues, with their naïve interpretations shedding new light on issues ranging from emotions like grief and love, through culture and politics.