Kian took to his Twitter page last night and wrote: Our little baby boy 'Koa' was born today at 6.10pm. Jodi Albert is an amazing woman. Love them both so much. Both doing amazing, so proud. X.'

He later thanked fans for their messages of support, admitting he was shocked to receive so many well-wishes.

He added: 'Wow thanks guys. Amazing to see our little boy Koa is trending in the UK! And he's only a few hrs old!!!'

And speaking to the Mail four hours after the birth, he said he was very tired and 'half asleep'.

He said: 'We had a long night last night so we’re both very tired. But we’re here in the hospital and all is fine.'

And a source close to the star said Kian has been on red alert for the past couple of weeks, opting to work from home in Sligo. He even chartered a plane home from London after the X Factor final, instead of staying overnight.

They said: 'He was never going to miss this. He is simply over the moon at becoming a dad.'

Kian's bandmates Mark Feehily and Shane Filan was among the first to congratulate the star.

And Shane added: 'Delighted for Jodi ,Kian and baby Koa Fantastic news!!! Congrats guys!!!'

Koa is a traditional Hawaiian name said to mean ‘brave’, ‘bold’, ‘fearless’ or ‘warrior’ and it is also a wood which is native to Hawaii and is used to make musical instruments, particularly guitars and ukuleles.