The 'What About Us' singer, 32, and her rugby player husband Ben Foden, 29, made their happy announcement via Instagram on Monday afternoon (8 September).
Una said: "I know lots of people have been guessing and Ben and I can now confirm that Aoife is going to have a baby brother or sister next year!
"We're all very happy!"
Una accompanied her post with a cute picture of her little daughter Aoife, two, wearing a T-shirt declaring: "I'm going to be a big sister!"
Congrats to Una and Ben!
Una's big news came the morning after The Saturdays kicked off their nationwide 'Greatest Hits Tour' in Scotland, taking to the stage in seriously dazzling sparkling outfits.
We're guessing all eyes will be Irish singer Una's stomach when they hit the stage tomorrow night in Newcastle...
Una and Ben's pregnancy news came the same day another pregnancy was announced - that of Kate Middleton! The Duchess of Cambridge and husband Prince William revealed today that they're expecting their second child together next year.
Stars who welcomed babies in 2014 in pictures!
Copyright: Rex Features WENN/Matthew Taylor/Daniel Deme/Josiah True/Matthre Taylor/Joe
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