NEW YORK - It's not always easy for child stars to continue their career into adulthood, or even puberty. For every Justin Timberlake, there's a Debbie Gibson.

That's why Miley Cyrus was so excited when her songs, "The Climb" and "Party in the U.S.A.," became bona fide hits on the pop charts last year. "The Climb" hit No. 4 on Billboard's Hot 100 chart while "Party in the U.S.A." stopped just short of becoming the No. 1 song in the nation.

While she has sold millions of records as an extension of her omnipresent Disney persona, Hannah Montana, those songs represented her biggest success to date as Miley — and she connected with more than just the tween audience.

"'The Climb' is the best thing that's ever happened to me," Miley said in a recent interview. "It went on ... every different kind of radio. I met everyone. I met 3-year-olds, I met 30-year-olds, I met 80-year-olds. ... I got so many different fans."

The 17-year-old phenomenon is on her way to duplicating that success with her new album, "Can't Be Tamed." The album's title track has already hit No. 8 on the charts.

But Miley is making more than a musical statement with the record. With songs like the title track and "Robot," she's sending a message of a young woman who cannot be controlled.

"It's all about breaking free, being who you are and not being afraid to tell the world to back off sometimes, and do your thing and do what makes you happy," she said of the CD.

What makes Miley happy, however, doesn't always make others happy. And the more she inches to adulthood, the more critics she seems to garner for behavior deemed age inappropriate.

There was the 2008 dustup over the Vanity Fair photo where it made her look topless, wrapped in a bedsheet (she says she was not). She danced with a stripper pole at the 2009 Teen Choice Awards. This year, video surfaced of Miley giving one of the producers of her film "The Last Song" a lap dance at the wrap party.

Earlier this month she simulated a girl-on-girl kiss while performing on "Britain's Got Talent," and on the Much Music Awards, she gyrated onstage while wearing a revealing outfit.

Joan Ulrich, of Northville, Mich., worries about the affect Miley's recent behavior will have on her young nieces.

"Their mom bought them tickets to see her show and they were so excited about her. They had her videos, T-shirts, the whole thing," she said. "Then she evolves into this sex kitten and there's no control with her."

But Miley brushes off her critics, deeming them unsatisfied and unhappy with their own lives.

"It's just kind of a sad thing to think about people and how they are. I never really let it affect me," she adds. "My mom is at the side of that stage and if I ever felt I was disappointing her or not making her proud, I would not do the things I do, but she's proud of me every time."

And Miley does have her supporters. Anthony Campiglia, of Clark, N.J., says the singer is doing nothing wrong by maturing.

"I think it's ridiculous for people to criticize Miley for growing up. She can't talk about puppies and lemonade forever. She's getting older and is naturally going to start acting and singing about older things," he said. "I just think it's up to parents to monitor and regulate what their kids watch."

Kids won't have the option of watching new episodes of "Hannah Montana" for much longer. Miley recently wrapped filming of the show's fourth and final season, which will begin airing in January 2011.

Miley says the show is ending because it has run its course.

"We would just destroy what we did if we continued to do it for too much longer, because it would become more of a kid show than a family show. It would be hard not to make it more immature," she said. "You've done 101 episodes. What else can Hannah get into?"

For its part, Disney has always publicly backed Miley. And if the company has ever had a problem with her, the teen isn't saying.

"I'm very open about being my own person. Disney Channel is a huge group and I'm very lucky to have worked with them," she said.

"But again like I don't care how big a company is. You can't say, `You can't do this' or`You have to do that,' because then I'm not an artist," she said. "Then you're a robot. That's not who I am. I don't classify myself (as) the face of what Disney needs me to be. ... I'm myself so otherwise they'd have to hire someone else, because I'm not that person."