On Saturday (25 October), Rebecca announced that she had given birth to a baby girl - her third child - and she has now posed for a photo with her.
Arabella is wrapped in a soft purple blanket in the snap and is nuzzling into her mummy's chest. Sharing it on Instagram, Rebecca has told fans just how much she loves the tot.
In an emotional post, the singer said: "Don't think I have ever felt so complete, snuggles with mummy. I am absolutely head over heels madly in love...
"With Arabella, I cry everyday with how unbelievably grateful I am for her little life. Arabella, you melt my heart #blessed #thankful #perfectangel #giftfromgod."
In February, Rebecca fainted during a live appearance on Loose Women and, two months later, she announced her pregnancy.
The 28-year-old is also mum to daughter Lillie May, nine, and son Karl, seven, from a previous relationship.
Rebecca starred on the seventh series of The X Factor in 2010 and came second in the final to Matt Cardle.
Celebrities who have welcomed babies in 2014:
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