So long as the universe had a beginning, we could suppose it had a creator. But if the universe is really completely self-contained, having no boundary or edge, it would have neither beginning nor end: it would simply be. What place, then, for a creator? - Stephen Hawking
Write about small, self-contained incidents that are still vivid in your memory. If you remember them, it's because they contain a larger truth that your readers will recognize in their own lives. Think small and you'll wind up finding the big themes in your family saga. - William Zinsser