Former X Factor contestant JJ revealed his happy baby news via Twitter on Wednesday night (18 September), writing: "Guys I want you to be the first to know that I've got some big news...I'm going to be a daddy.... :-) :-) wooop x."
The 25-year-old later added: "My girlfriend and I are super super excited and the boys cant wait to be uncles! They are already thinking of names begining with J lol."
Of course, the singer's bandmates were the first to congratulate him.
Josh Cuthbert wrote: "SUPER DOOOPER WOOOOPER HAPPY FOR MY BROTHER JJ :-) :-) :-) :-) hi my names Uncle Josh......just call me Uncle.Pidge. :P hehe! Love you bro x."
Jaymi Hensley added: "Congrats JJ & Cat - gonna be an uncle whoop."
After receiving congratulatory messages from the bands one million plus followers on Twitter, JJ wrote: "Off to bed a happy chappy!! Thanks for all your amazing support and kind tweets much love to all of you your amazing xxx."
It's a busy time for Union J, who are preparing for the release of their debut album next month. The first single, 'Carry You', entered the UK charts at number six earlier this year.
More celebrity babies on the way in our gallery below!
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