What makes a story is the ability it has to relate to the reader. The power you get from a story is how you are able to relate it to yourself.
Grown up is an undefined state, which heavily involves life goals and dreams. Growing at different paces, we are all trying to grow up to be something.
In our head, princesses have specific qualities. But aren't there exceptions for all of them? What princess are in your life? What princesses do you write?
Characters in a story have a deep and dark place in their story arcs. We have them in our lives as well. Do you know yours, or better - the solution?
Ideas don't drop out of the sky fully developed. A process of ten hundred beginnings is what develops ideas. Take the snippet you have and run with it.