According to HPANA, Daniel Radcliffe has issued an invitation to President Obama's two daughters, Sasha and Malia, for a personal tour of the Half Blood Prince set, and would serve as their personal tour guide.
The President's daughters are big fans of the books, with their father reading it out lout to them. For more click here. For a look at the article in The Daily Beast, who interviewed Dan, click here.
I'm glad to see the young minds of America, including the President's family, are not being poisoned. Yeah Obama! You read them Harry Potter!