05/16/2011 at 01:00 AM EDT
Officially, he was the best man. Unofficially, Prince Harry
had another role: court jester. He kept his brother jolly before the ceremony, joked with his grandfather Prince Philip on the palace balcony and minded the littlest members of the wedding party during their carriage ride. At the Queen's reception, Harry "had the young flower girls in tow around his legs," says Prince Seeiso of Lesotho. Observes wedding guest Amanda Berry: "He looked as if he was enjoying the whole event."
Did anyone expect otherwise from the boy whom his late mum, Princess Diana, used to call "the naughty one"? From the moment he sauntered coolly down the church aisle, Harry put his stamp on the day. "He did his best-man bit very well," says family friend Alex van Straubenzee. Not only did Harry host William's stag party in March, he played the emcee during the evening reception, introducing Michael Middleton and the groom's friends Thomas van Straubenzee and James Meade before their speeches. His most memorable contribution, however, may have been his own toast. "He was fantastic," says an insider. "It was humorous, witty-just brilliant. He just seems like the best brother anybody could ask for."
The princes always have been exceptionally close. "We can talk about anything," Harry has said. "We understand each other." As for his feelings about Kate, Harry has said he is "delighted" to have her join the family. "It means I get a sister, which I have always wanted."
Harry, who is third in line to the throne, is now the U.K.'s most eligible bachelor. Though his on-and-off girlfriend Chelsy Davy (see below) was in attendance, fans of the ginger-haired prince can still dream they might nab him for themselves. Says Holly London, 19, of the Middletons' hometown of Bucklebury: "My friends and I just hope that Harry stays single for a bit longer so we have the chance to become a princess too!"