How did wendy know she'd grow up

Wendy knows that growing up is an inherent part of life and understands the responsibilities that come with it.

Explanation:

you shopuld find your answers here if you need more. the answer is the infinite variety of human nature

reading poetry is challenging when you don't have or very little of social context and culture schema.

solution: read the introduction, the norm, or even explaination if you still dont get it.