Are they really brothers?
Indeed they are! Kevin (full name: Paul Kevin Jonas II, birthdate: November 5, 1987), Joe (full name: Joseph Adam Jonas, birthdate: August 15, 1989) and Nick (full name: Nicholas Jerry Jonas, birthdate: September 16, 1992) are all the sons of Paul Kevin Jonas Sr., a former minister and musician, and Denise Jonas, a teacher and singer.

Why did they start a band?
Mostly because Nick needed backup singers. Nick got his start on Broadway at the ripe old age of seven; by the time he was 12, he was signed to Columbia Records and working on a solo album. Kevin and Joe stepped in to help him write and perform a few original songs, and while the album was basically shelved, Columbia execs were sufficiently impressed with the boys to sign them as a band. Within two years, they had toured with the Backstreet Boys and the Veronicas, and released their debut album, It's About Time.

How did they end up on the Disney Channel?
Following the release of It's About Time, the Jonas Brothers recorded two songs for Disney projects and toured with Disney girls Aly & AJ, while their slightly cleaned-up cover of Busted's "Year 3000" topped the Radio Disney charts. So when Columbia dropped them in 2007, Disney's Hollywood Records picked them up and fed them into the Disney machine. The boys guest-starred on Hannah Montana, appeared in music videos and featurettes during Disney Channel commercial breaks, toured with Miley Cyrus and starred opposite Demi Lovato in the Disney Channel Original Movie Camp Rock. And like most kids in the Disney stable, they got their own TV show, JONAS. (Early in its development, the title stood for "Junior Operatives Networking As Spies," but eventually it stood for... well, nothing, as the spy conceit was abandoned and the guys just played rock stars.) Disney knew what they were doing: while It's About Time had sold less than 100,000 copies, the band's power-poppy self-titled second album was certified double platinum and their next two albums, A Little Bit Longer and Lines, Vines and Trying Times, each hit No. 1 on the Billboard album chart.

Are there any more Jonases I should know about?
The boys have a younger brother, Frankie, sometimes known as "the bonus Jonas." Frankie isn't in the band, but he has appeared in his brothers' music videos and television projects.

What's with the diabetes jokes?
Nick was diagnosed with Type 1 diabetes when he was 13 years old. He's worked with a number of organizations to raise both money and awareness for juvenile diabetes, and appeared in front of the U.S. Senate to request an increase in funding for diabetes research.

How did they get Russell Brand in trouble?
Early in their careers, the Evangelical Christian brothers wore purity rings and spoke openly about abstaining from premarital sex. During the 2008 MTV Video Music Awards, host Russell Brand mocked the idea that a band with so many female fans would remain abstinent, and claimed to have deflowered one of the brothers backstage—and boy did it make Jordin Sparks mad. She wasn't the only one: Brand took a lot of heat from both the public and the press for his comments, as well as his less-than-flattering description of then-President George W. Bush.

Really, though, no sex until marriage?
That's what they say.

So how are their love lives?
Kevin married his girlfriend Danielle Deleasa in December of 2009; his brothers served as his best men. Nick dated Miley Cyrus, though they didn't confirm their relationship until after they broke up, and fellow Disney star Selena Gomez, though they didn't confirm that relationship at all. (Selena has since begun dating-but-not-confirming-that-she's-dating Justin Bieber.) And Joe appears to be the worst boyfriend a girl could ever have. He rather infamously dumped Taylor Swift with a 27-second phone call, and after months of speculation, he and Demi Lovato confirmed that they were dating in a Teen Vogue interview—then broke up in the same interview, leaving Demi to imply that she was blindsided by Joe dumping her. Joe, meanwhile, moved on to Twilight star Ashley Greene, and brought her along on the subsequent Jonas Brothers / Demi Lovato tour. (Ashley's presence on the tour was rumored to be one of the reasons behind Demi's breakdown and entry into rehab.)

Besides breaking hearts, what are the boys up to now?
Kevin is taking time off to be with his wife, while his brothers are both starting solo careers. Nick formed a new band, Nick Jonas & the Administration, with producer John Fields and a few former members of Prince's New Power Generation. They released the mildly bluesy, slightly-more-soulful-than-the-Jonas-Brothers album Who I Am in early 2010. Joe, meanwhile, is working on a dance-pop album with producer Danja, who's also crafted songs for Britney Spears and Usher.

Oh God, are they breaking up?
They say they're not, even though they have no immediate plans to record as a band again. So, you know, have hope.