The former Girls Aloud star and her long-time boyfriend Justin Scott welcomed their first child together, son Bobby, on Thursday, 4 September.
Announcing the happy news on Twitter today, the singer said: "Our beautiful baby boy Bobby arrived yesterday afternoon. He's perfect."
Best friend Cheryl Fernandez-Versini was quick to reply: "He really is. He's perfect!"
Guess Cheryl's already been round to see the new arrival!
Also sending well wishes was Kimberley's close friend Denise Van Outen who tweeted: "Beyond happy for you and Justin. Had a feeling you would have a boy! Enjoy every second."
Kimberley, 32, had not publicly revealed the sex of her baby ahead of the birth but fans had guessed it would be a boy because she'd Instagrammed a picture of blue baby clothes.
Fans had wondered if Baby Walsh-Scott was on the way as Kimberley hadn't tweeted since 30 August, when she gave a shout-out to best friend Cheryl Fernandez-Versini's return to X Factor.
Kimberley announced her pregnancy in February, saying: "Justin and I are so happy to let you all know we are having a baby!!! Couldn't wait to share our lovely news with you all." Kimberley also posted icons of a baby and baby bottle.
The 'Love Machine' singer had been doing pilates and yoga in the run-up to her delivery date, saying it had been keeping her active and strong.
She's planning to have a quiet end to the year, focusing on life with her baby and a "cosy" family Christmas. 'It's the one time in my life where I can take time out and not plan."
Congrats to Kimberley and Justin!
More stars who've welcomed babies in 2014!
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