I don't think we can every unsee what is seen or unknow what is known. And I believe that is why all ancient religions sometimes looked at knowledge as a way to misery. It is not possible to live ignorant. But knowledge brings it's own burden and we can never go back to the novice state.
My mother used to say an old phrase from her native land - only the foolish and the genius don't fear exams.
For most people in the middle worry and fear is always present and both can be major obstacle to innocence and kindness.
Also I don't always consider innocence to be a virtue. For eg. some of the meanest things which happen, happen between kids. Mainly because they don't know better.
So I guess what I am saying is it is complicated at all ages, but you already know that :D
Hmmmmm... It is indeed complicated at all ages.