It's a little confusing, because this means that the books were written after the facts they described actually happened. And, understandably, many of us who are not currently 33 felt like we were growing up with the books as we read them. As a gift, he's getting this brand new cover for The Deathly Hallows, created by Kazu Kibuishi.
Anyways, happy birthday, Harry, symbol of eternal youth and innocence and goodness. Hope you're doing okay with your normal, post-Voldemort life, rather than having some kind of mental breakdown because you don't know what to live for when there isn't a perfectly-timed battle at the end of every school year.