LONDON, England --Powerful husband? No problem. Money? Got that too. Clothes, good looks? Ditto. What does the woman who has it all do after her honeymoon? That's a tough one. Kate Middleton's fame is undeniable. She is already one of the world's most talked-about women, and that will only increase when she marries Prince William next month. But her royal role remains completely undefined, and much rests on her slender shoulders. If her marriage to Prince William is a joyous union that produces heirs, not tears and recrimination, the young couple could put the somewhat shaky British monarchy on solid footing for generations to come. But if it collapses into a replay of Prince Charles' I-hate-you-I-hate-you-more donnybrook with Lady Di, the impact on the House of Windsor would be grave. Journalism professor and newspaper columnist Roy Greenslade said William and Middleton must rebuild public trust that has been eroded by heir-to-the-throne Prince Charles -- because of his failed marriage and perceived eccentricities -- and by scandal-bound Prince Andrew. The British public still reveres the queen, he said, but has doubts about her four children, including Princess Anne, who is divorced, and the nondescript Prince Edward. "The glue that holds the monarchy together is the queen, but there is a great deal more skepticism and even cynicism about the next generation," he said. "You have a dysfunctional family, so it really falls on William and Kate to actually be an upright couple that can engage with the public and be glamorous at the same time. It's fine with the queen on the throne, and Charles won't reign for long, so it really does fall to the next generation to rescue them." Restoring the frayed bond between crown and subjects is vital, Greenslade said, because the monarchy will suffer a substantial blow when the queen dies, and also faces the very real threat that Australians will decide to sever ties to the British monarch in the next decade, likely giving republicans in Britain a boost. That's a lot of pressure for a young woman who already faces the formidable task of marrying into a rather imposing family. She will be expected to support William as he takes on more royal duties -- like his trip this week to Australia and New Zealand, where he is serving as the queen's representative. Middleton will also serve as an articulate (and photogenic) link between the public and the royals even as she tries to master the mysteries of married life. "Her prime objective is to become a wife, and a good wife," said Dickie Arbiter, a former royal spokesman who expects Middleton to give up her nightclubbing ways once she becomes a princess on April 29. "People are judged by what they do," he said. "She knows what is expected of her when she marries into the royal family. There is an element of royal duty that is expected of her, just as it was of Princess Diana, and she knows that." The British public expects its royals to earn their keep with a nonstop series of appearances in exchange for the considerable benefits the royals receive each year. Arbiter said Middleton is likely to take up charity work in earnest, picking the causes she really wants to promote, but could instead decide to put everything on hold and concentrate on starting a family. He said the royal couple won't need a "getting to know you" phase because they have already lived together for some time in the years since their romance started in college. To say there would be strong public interest in her children is an understatement. It seems like a distant memory from a more innocent age, but there really was a national outpouring of joy when Princess Diana gave birth to William in 1982, giving the nation a new future king and extending the royal family's continuity to a new generation. Middleton's first male child -- or her first daughter, if there are no sons -- would also be a likely future monarch who would follow William to the throne. Parliament has briefly discussed changing the rules in the name of gender equality so that William and Middleton's first born child would keep his or her place in the line of succession regardless of whether it is a boy or a girl, but the rules giving males preference are likely to remain unchanged. It is not easy to change the rules, even if they are antiquated by today's standards, because so many Commonwealth nations that recognize the queen as head of state would have to give their assent. There has long been speculation that William hopes to modernize and streamline the British monarchy, which clings to its traditions and prerogatives more than most of its counterparts throughout the world, but the likely future king has not spoken out in public about his plans and goals. To do so would be seen as a major breach of protocol, since his grandmother is the reigning monarch and his father is next in line. It may be many years before William gets the chance to make major changes, and of course he may change his views as he moves into middle age. Little is known publicly about William's personal views, in part because he has been very guarded with the press, which he blames for hounding his late mother in her final years. In a legal sense, Middleton will not have a constitutional role in British affairs until she becomes queen, which can only happen when William takes the throne as king, an event likely to be far in the future since William's father, Prince Charles, is ahead of him in the line of succession. In practical terms, Middleton may be a princess for decades, but her status as a likely future queen will focus extra attention on everything she says and does, just as it did with Diana, who promoted on numerous charities during her long years in the public eye. There seems to be abundant public goodwill for William and Middleton as they near the altar. Some people say they are bored with the upcoming event -- and tired of all the publicity and speculation about dress designers, guest lists and the like -- but there does not seem to be hostility directed toward the couple, who are seen as genuinely committed to one another, not just faking it for the cameras. Keiren Buchanan, a Londoner who works in communications, said Britons have warm feelings for William that should smooth things out for Middleton as she adjusts to life inside the royal goldfish bowl. She believes Middleton should concentrate her energy initially on charitable works designed to ease the burden for Britons who have suffered because of the global economic downturn. "Kate Middleton should bring it back to Britain, start in her own backyard and really focus on the most pressing issues here, whether it's about homelessness or poverty," she said. "There are a lot of economic issues here." So Middleton's top tasks are simple come April 30: Rejuvenate the monarchy, end poverty in Britain, have kids, and make sure her marriage is a success.