J.J. Hamblett uses parenthood to get out of things he doesn't want to do.

The Union J singer is proud to be a father but his bandmates - George Shelley, Josh Cuthbert and Jaymi Hensley - admit he has changed since girlfriend Caterina Lopez gave birth to their son Princeton last November.

Josh said: ''He likes saying it, he likes saying, 'Yeah, I'm a dad now'.

''If there's ever anything that the record label wants us to do that JJ doesn't agree with ... so if they're like, 'Guys, you need to act really kiddy and funny' - JJ is like, 'I'm 26, I'm a dad and I can't do this'.''

The 'Beautiful Life' singer previously expressed his intention to juggle his career and family life, citing former JLS singer Marvin Humes - who has 14-month-old daughter Alaia-Mai with wife Rochelle Humes - as a good example to follow.

Speaking before the birth of his son, he said: ''Well, that's the thing, there's so many people like Marvin who, although JLS are splitting up, he's still doing 'The Voice', he's still DJ'ing all the time, he's away 24/7 but you've got to make small sacrifices. The harder we work the more successful Union J will be, the better life the kid will have.''