Northern Irish singer Nadine, 28, announced her pregnancy via Instagram on Thursday morning (15 August) by uploading a picture of herself with the words "I'm having a baby" emblazoned across it.
She will be the first Girls Aloud star to become a mother.
Cheryl congratulated Nadine via Twitter later in the day, writing: "I just woke up to the news that there is to be a baby aloud!! This is so crazy. But amazing!!
"Congratulations @nadinecoylenow. Can't believe you're going to be a mummy!!!!!!!!!!!"
Cheryl had just jetted into Los Angeles from the UK when Nadine announced her pregnancy. Coincidentally, Nadine lives in LA so perhaps the two will meet up for a proper congratulatory catch-up?
Fellow Girls Aloud star Nicola Roberts has also sent her congratulations.
Nadine has yet to reveal who her baby's father is.
Pregnant celebrities in pictures!
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