Dressed in a festive sequinned vest, the beautiful Irish singer (and bump!) hit the stage with The Saturdays for Radio City's Christmas Live concert at Echo Arena on Wednesday (10 December).
Una, husband Ben Foden and daughter Aoife are preparing for their last Christmas a trio, with Una and Ben's second child due next year.
The couple have already revealed it's a baby boy.
Una announced her pregnancy back in September, just a day before The Saturdays kicked off their nationwide 'Greatest Hits Tour' to promote their Greatest Hits album.
Meanwhile, things have been getting festive in the Foden household. Already, popstar Una has treated little Aoife to a visit to Santa's Grotto and taken her to the premiere of Christmas family film Get Santa in London.
The Saturdays recorded a Christmas song for the movie - a cover of The Waitresses' classic 'Christmas Wrapping' - which is available via YouTube and on the movie's official soundtrack now.
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