Jonas Brothers, Justin Bieber Jonas Brothers, Justin Bieber

Is Bieber fever eclipsing the JoBros?

The singing siblings may be losing their hold on the tween and teen market, according to Disney internal market research acquired by The Daily Beast.

Just two years ago, the Jonas Brothers' manic fan base launched the Kevin, Joe and Nick to superstardom. But in the past year, their album sales, 3-D concert film and new Disney show Jonas have all taken a hit in sales and ratings. Worse, Disney's focus-group research showed that while 8- and 9-year-old girls are still into the clean-cut rockers, some 9- and 10-year-olds said they would be embarrassed to talk about the Jonas Brothers with other friends. Young teens were more harsh, saying they were less interested in the JoBros than they had been six months earlier. One participant said if you wear a Jonas Brothers backpack to school, "other people might think you're dorky."

Watch full episodes of Jonas

Meanwhile, 16-year-old pop/R&B singer Justin Bieber is quickly becoming the 'it' kid in the tween demographic. "I think it's something of a changing of the guard in terms of a teen pop crush," Billboard senior editor Ann Donahue told The Daily Beast. "Justin Bieber is definitely the next new thing and is overshadowing the Jonas Brothers. But Bieber doesn't have the marketing power of Disney behind him, which can't be discounted."

Woman in bar mistaken for Justin Bieber

A Disney spokeswoman told The Daily Beast that the median age of the Jonas Brothers' fan base is 16. She also said the network is making efforts to revamp the Jonas Brothers' image by transforming their Disney Channel show, which is now titled Jonas L.A. and mirrors the popular HBO series Entourage.

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