The pair announced on Instagram that they welcomed their first baby into the world on October 1st

Westlife's Mark Feehily and his fiance Cailean O'Neill have welcomed their first baby.

They announced the happy news on Instagram, and revealed that they've named her Layla.

The 39-year-old singer revealed that they are the "happiest dads in the world" - and shared an adorable picture of them carrying the newborn out of the hospital.

He captioned the pic: "Baby Layla born safe & sound @ 7.27pm on October 1st 2019!

Baby Layla born safe & sound @ 7.27pm on October 1st 2019! We’re the happiest Dads in the world! ❤️👶🏻🇮🇪🌈 😘 x

A post shared by Mark Feehily (@markusmoments) on Oct 2, 2019 at 10:49pm PDT

"We’re the happiest Dads in the world!"

Fans rushed to congratulate the new parents, with one writing: "Congratulations darling, welcome to the world baby Layla."

Another added: "Congratulations! She is gonna be so loved!"

And a third wrote: "I am so happy for the both of you."

Just test driving the new wheels!

A post shared by Mark Feehily (@markusmoments) on Aug 17, 2019 at 1:29am PDT

Mark announced that he was expecting a baby back in May on his birthday.

He wrote: "It really makes this my most special birthday EVER to let everyone know that later this year we will become Dads for the first time.

"This is the proudest moment of our lives and we are beyond excited to say it out loud!"

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