The personal statement is really something very personal. It's about the parts of yourself, your life, your personal experiences that you think that would be relevant, and they will surely be very different from person to person.
Different universities also like to see different kinds of people. Harvard may like examples of leadership, while Stanford prefer to see unusual experiences, for example.
So, I don't think anyone can really give you a good list of questions and categories. It's not like a statement of purpose, when there are specific things you are expected to cover, like "why a PhD?" or "what are your research interests".
And personal statements are not so relevant for PhD applications anyway. I think I didn't send one for most of schools I applied to. The statement of purpose is the relevant one, not the personal statement.