Tonight, "20/20" has an all-access pass behind the scenes of everything Jonas -- and "The Insider" has an exclusive first look!
"I went in to the doctor -- my lifelong pediatrician," explains Nick of his life-changing news. "She heard my symptoms and had this look on her face and just said, 'Okay, we're going to need to test your blood sugar.' And I was like, 'Huh, which finger, you know? Because I play guitar, so I'm going to make sure I don't do these things that are going to hurt me.' And she's like, 'It doesn't matter.'"
Once the blood test came in, Nick learned that he would be living with diabetes.
"Surely enough, my blood sugar was over 700; normal's about 70 to 120, so it was a lot higher than it should have been."
Airing at 10pm on ABC, “20/20” correspondent Juju Chang gets personal with Nick, 15, Joe, 18, and Kevin, 20, to discuss fame, music, rumored romances and coping with Nick's illness.
Watch "The Insider" for more with Nick and The Jonas Brothers.
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