It's because it's a question. In Spanish, most questions, especially those that start with the English "Wh-" words (like where, who, what), have reversed order for subject and verb. That is, the verb should come right after the question word and the subject comes next.
We almost do this in English, except we put a "do/does" or similar word right after the question word instead. Like "Where does your sister live?" or "What does Charlie want?"
Technically not true Daniel, although the forms without the helping verb are bound to sound old-fashioned and "strange" to modern speakers.
As an example, consider the nursery rhyme: "Baa baa black sheep, have you any wool?"
Will we say this is incorrect, and force children to sing "Do you have any wool?" :)