The S Club 7 singer and husband Alex Bourne announced their happy news on Tuesday night (1 April), revealing their second child had arrived that day weighing 7lbs 7oz.
She hasn't been named yet.
In statement, the couple - who are already parents to daughter Amelie, three - said: "We're so happy that baby has arrived safely. Within minutes of meeting her we were totally smitten.
"Amelie is happy and 'cited to have a little sister to play with and we can't wait to introduce her to the whole family."
Alex also confirmed the birth via Twitter, writing: "Delighted to announce the safe arrival of our gorgeous little girl! @MsRachelStevens and baby both really well. Amelie happy and 'cited."
Just a few days ago on 24 March, gorgeous Rachel had tweeted a picture of her bare stomach, alongside the caption: "BABY BUMP - I'm starting to nest as it's not long to go now!"
Congratulations to Rachel and Alex!
Rachel's not alone! More stars who've welcomed babies in 2014 in pictures:
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