From the first page of Number the Stars, Ellen and Annemarie are set up as a classic case of opposites attract: one's blonde and one's brunette, one's tall and one's short, one's an athlete and one's an actress. Later we find out that they're also different in terms of religion: one's a Christian and one's a Jew. But none of these differences matter to the two girls. In fact, their friendship even acts as a foil to the Nazis' actions. The Nazis emphasize difference so they can stamp it out, while Ellen and Annemarie relish in their differences.