The Jonas Brothers' father Kevin Jonas Sr is battling colon cancer.

The 52-year-old father of the former pop group - comprised of Kevin Jonas Jr, 29, Joe Jonas, 27, and Nick Jonas, 24 - has revealed he was diagnosed with the disease in March and has since undergone surgery on the affected area.

Kevin - who also has 16-year-old son Frankie Jonas with his wife Denise Miller-Jonas - said his sons were understandably ''shaken'' when he received the diagnoses, and all rushed to be at his side as he was taken to hospital.

He said: ''They were shaken. Frankie came home from school, Nick came from LA, Joe flew directly from Japan - they cancelled their schedules, moved important things. They stayed with us, last meal before surgery. They walked me into Sloan Kettering [Cancer Centre in New York City], which created a little bit of a stir.''

Kevin has yet to undergo chemotherapy treatment but claims his prognosis is looking good, and has said he decided to open up about his diagnoses because he felt a ''responsibility'' to make sure people are aware of this particular strain of cancer.

He added to local news channel NBC Charlotte: ''There's also a feeling of responsibility to others. I waited two years past that 50 year mark.''

Meanwhile, Nick Jonas - who was diagnosed with diabetes when he was just 13 years old - recently claimed he wants to use his diagnoses to ''encourage'' young people to overcome their own ''struggles''.

He said: ''This is a disease I was diagnosed with when I was 13. It was a moment in my life when I was just getting ready to start making music with my brothers, and touring, and it was something I thought would slow me down before I even got started.

''Thankfully it didn't, and I'm in the healthiest place I've been since my diagnosis. But when I found out I would be receiving this award, I started thinking about who some of my heroes are. Not the kind of heroes who wear capes and save cities from evil villains, but real people who are heroes because they've changed the world in some way and made it a better place, or people who directly impacted my life.

''We all have the power to change the world and make it a better place. Every day can be an opportunity to be a hero. [If] you're kind to someone who needs it, or you find a cause you're passionate about. You get involved with something and raise your voice in some way. It does make a difference and I would encourage all of you to do that.

''What I saw as the biggest challenge of my life really did become the biggest opportunity to bring some encouragement to people like these amazing kids and hopefully people like you who are going to have your own struggles in your life.''