From the Huffington Post:
Grown-ups tend to think their problems are bigger and more important than the trials kids experience, but guess what? They're not. We're all traveling through life together--and not only that, but every adult was once a child. Too many adults forget that, I think. Too many adults forget what it feels like to be that awkward middle schooler worrying about which table to sit at during lunch. They forget that dealing with changing bodies, ever-shifting friendships, and maybe-getting-divorced parents is hard. So hard. I write about all that stuff (and more), but I don't write with the goal of corrupting my readers. I write with the hope of handing my readers a mirror in which they can see themselves as well as a window through which they can see the pains and joys of others.
Relatedly: Her 2013 AMA at reddit.