[Harry has just successfully conjured a Patronus]
Professor Lupin: You know something, Harry? I think you would have given your father a run for his money, and THAT is saying something.
[beat]
Harry: I was thinking of him... and Mum. Seeing their faces. They were talking to me, just talking. That's the memory I chose. I don't even know if it's real. But it's the best I have.