The play was fast and the score tight as the tallest member of Highgrove's team chased the small wooden ball across a polo field in Gloucestershire, England. Raising his mallet, he took dead aim, swung--and missed completely. "Oh, come on!" a distressed teammate growled, before charging off to follow the bouncing ball.

That brief, spontaneous and altogether unremarkable interplay between two teammates would hardly have stirred notice, were it not for the athletes involved: Princes William (the Flubber) and Harry (the Decrier). Along the sidelines charmed spectators no doubt wondered if Harry, 16, had been encouraging William, 19--or seizing a rare public opportunity to rag on his older brother. As commentator Jim Hilston had quipped over a loudspeaker, "That Prince Harry sure likes to get into a tussle."

If so, all evidence of brotherly competition faded as soon as the boys--playing publicly for the first time with their father, Prince Charles, 52--exited the field in triumph. Afterward, in William's VW Golf, they drifted naturally to their symbolic positions: William in the driver's seat (an attractive blonde female at his side), Harry relaxing in the rear.

Boys no more, the British princes are not only maturing gracefully into manhood, they seem to be growing into a comfortable and supportive relationship that erases the 27 months between them. "As they get older, the age difference diminishes and they get closer," says Peter Archer, royals reporter for Britain's Press Association. "They genuinely enjoy each other's company."

And perhaps each other's differences. Keenly aware of his place in the royal lineup, the shy and introspective William remains a classic first son, responsible, serious and controlled. "William very much plays up to being the older brother," says a friend. "He looks out for Harry." The more volatile Harry continues to be easygoing and carefree, often looking to William to take the lead. "I think Harry is quite happy being second," suggests another pal. Still, Harry's fiery side can flare when he feels overshadowed or put down by his big brother. "William might occasionally tell him not to be stupid or have a laugh at his expense," says a family friend. "Like all brothers, they do have cross words, but they are a good support for each other."

And each, more than anyone else in the world, is in a position to know just how the other feels--about being in the spotlight, about the blessings and burdens of growing up royal, about losing a parent who was both the most famous woman in the world and, more simply, their mother. "They need each other in terms of moral support," says a friend of William's. "Since the death of their mother, even more so."

Their bond is based on more, of course, than shared pain. Both William and Harry love polo, country weekends spent with horses and hounds (when William sees a dog, he bounds right up to it, says a friend), and hanging out at fashionable London night spots.

And both also seem to possess similar tastes in female companions. Tall and slim, with long blonde hair and hyphenated last names, their teenage gal pals look virtually interchangeable in the grainy, long-range shots captured by paparazzi. William is often found in the company of young women like former PR agent Natalie Hicks-Lobbecke, 23, or Davina Duckworth-Chad, 22, a cousin. Both young women are members of the princes' elite social gang. "They all know each other," says Brian Hoey, author of 15 books on the British royals. "Their parents know each other. Their grandparents know each other."

Another of those linked to William is Emilia d'Erlanger, 19, the granddaughter of a viscount. Known to her chums as "Mili," the blonde beauty is said to share William's love of art history. Though she, like William, is expected to enter Scotland's University of St. Andrews in September, a friend insists, "romance is out of the question." And indeed at present, Mili appears to be equally chummy with Harry, with whom she sat at a July 29 polo match in Cowdray Park, south of London.

Around such stunners, Harry can turn playful and exuberant. He nodded and laughed when the hot dog vendor at a recent polo match offered to set him up with her teenage daughter. After another match in Gloucestershire, he let salesgirl Lizzy Ward, 17, ruffle his hair, and he roughhoused with Emma Lippiatt, 19, swirling her around, hoisting her over his shoulder and planting a kiss on her cheek. And he has been known to make off-color quips. "He has the smutty humor of his mother," says a family friend. "She used to love telling smutty jokes."

Harry has also inherited Di's gift for reaching out to people. At Nam Long Le Shaker, a Vietnamese bar and eatery in Kensington whose glittery clientele includes Hugh Grant, a bartender admits with a sheepish grin, "I like Harry better. Harry comes and talks with me; William is more reserved." (Harry, who is still under the legal age of 18, does not drink on these outings.)

When William does the town, he sticks with his group, drinks moderately--at the Vietnamese joint, he favors White Panthers (a concoction of sweet liqueurs) and banana daiquiris--and refrains from dancing. Even at trendy nightclubs like K-Bar and 151 Club, "William is terribly careful, so he would not ever be in a position where he could be compromised by having a romance or whatever," says a friend. The palace denies press reports that the prince smokes cigarettes on such occasions.

Despite the brothers' differences in style, the public image of William as the academic son and Harry as the athletic one is blurring. Though hard-working William easily surpassed the grades required for admission to St. Andrews, a friend says, "William is not a brilliant student, but he was able." In sports, he holds his own, having captained the Eton swim team and competed in soccer and polo. (That missed shot in Gloucestershire was a fluke; it required a right-armed shot, and he's a lefty.)

Harry, who is doing fine at Eton, excels at rugby and skiing and is the more natural of the two at polo and hunting. Following a growth spurt that has left him 6 ft. tall, he is coming into his own as he uses the polo field to challenge not only his 6'2" brother but his 5'10" dad as well. "Harry is certainly at an age where he wants to prove himself against the world," says polo commentator Hilston. "So you see good rivalry between father and son."

Off the field, both boys enjoy a close relationship with Charles, whom they see at least once a month during the school year. (The trio are spending August at the Queen's Balmoral estate in Scotland.) "He's emerged as a very successful single parent," says royal watcher Hoey.

The family circle has expanded to welcome their father's longtime love Camilla Parker Bowles, 54, who now has her own rooms at Charles's two main residences, St. James's Palace in London and Highgrove, his country estate in Gloucestershire. "They get on with her quite well, William perhaps slightly more than Harry," observes Hoey, who says that when Charles is not present, the boys often chat with Camilla. Contrary to speculation that William has at times felt like a pawn in his father's campaign to burnish Camilla's public image, a source close to the royal family concurs that relations between Camilla and William are "social, warm and friendly." A family friend adds that the sons "want what is best for their father. She is what makes him happy, so they are happy with her."

It is not known to whom the boys unburden their feelings about their mother, whom they never discuss publicly. One possibility is Diana's brother Earl Spencer, 37, who sees his nephews a few times a year. "William and his uncle have a good rapport," says a friend of Spencer's. On July 1, which would have been Diana's 40th birthday, William joined his uncle at Althorp, the Spencer family home, and together they rowed across the 40-ft. lake to the small island where Diana is buried so he could lay a bouquet of white lilies--his mother's favorite flower--on the grave. The visit, says a friend, "shows that the scars are healing."

Harry, who, at Eton, "would break down in a flood of tears" over his mother's death, says a friend, opted to remain at Highgrove, but friends say he too has learned to cope. "I think they've adjusted brilliantly," Hoey says of the boys' life post-Diana.

For now the young princes seem intent on living in the moment. While Harry finished up his year at Eton, William spent most of the year traveling the world, most recently touring Tanzania, Kenya, Mauritius and Botswana, where he saw wildebeest, black rhino, leopards, antelope and crocodiles. Ian Craig, who hosted the prince at a 45,000-acre private game preserve in Kenya, told The Sunday Times, "He did everything from rhino spotting to antipoaching patrols to checking fences."

When he returned to England in June just days before his 19th birthday, William was bronzed and upbeat. "It was good for him to be away from the madding crowd for a long period," says a friend. "He has done a lot of growing up." Even so, men will be boys. When William encountered paparazzi while out with friends for a night in London on July 25, his chums formed a protective shield and scowled while the grim-faced king-in-waiting pulled his blue baseball cap over his eyes--no doubt wishing he could preserve the privileges of youth a bit longer.