One word for a curious child
The adjective 'inquisitive' may be what you're looking for. It is defined: 'having or showing an interest in learning things', a synonym being 'curious'. As a person who shows an interest in learning, questions (which admire people like you) are likely to be second nature to them.
It also means 'unduly curious about the affairs of others; prying' (May be seen as a negative).
From the above, you could call the child 'inquisitive', or 'posiquisitive' to make it, the noun, aptly positive.