Friends say it only seems Harry parties a lot, because photographers are always close by. Photo by: RICHARD YOUNG / REX USA
A Tale of Two Princes| Prince Harry, Prince William
So which is it, Prince Charming – or Party Boy? Neither, insists the palace. "He is not a party prince and he is not a saint," says the prince's spokesman Paddy Harverson. "Most ordinary people think he is a thoroughly decent guy who every now and again gets into the papers because he goes to a nightclub."

Still, the prince Diana called "the naughty one" has supplied those papers with juicier material than big brother William, 22. As Charles and Diana's sons mature into young men, their personality differences are standing out more and more. "They are chalk and cheese," says a family friend. An avid athlete with a daredevil streak and charm to spare, "Harry is more impetuous than his brother and wears his heart on his sleeve," says this friend. William, meanwhile, "is remarkably mature," says a palace source. Those who know Wills describe him as serious, thoughtful and cautious, combining his father's passions with his mother's strong will. And yet, says royals expert and author Robert Lacey, "there's a calmness about him that neither his mother nor his father had."

Calm isn't exactly Harry's strong suit. While William has hit the books in the relative shelter of Scotland's University of St. Andrews, Harry has been having a post-high-school "gap year" to remember – or, occasionally, to forget. He has downed watermelon martinis in London's trendier night spots, smoked cigarettes out the window of Australian pubs at 4 a.m., smooched pretty girls on several continents and, most recently, weathered an allegation by a former teacher that he had cheated on a graduation exam at Eton (the school and the palace denied it).