Ideas and possible themes to be expanded:
Child is uncorrupted by socialization, therefore the child is more honest. Less tied down by expectations and personal cynicism. You get opinions and actions that are unfiltered
In raising a child, a parent learns personal responsibility. The former child (parent) is forced to mature, since he/she is responsible for a young life.
We see our own reflection among younger children, and in youth in general. There is a phrase...be childlike, but never childish. Meaning, dont be immature, but in that same vain dont lose that childlike spirit of imagination, wonder, and appreciating the joy of the littlest things --- which children often do. Children teach us those lessons daily --- to remain diligent in maintenance of that sense of being, which is difficult in a cruel, adult world.
---Hope that helps.