Earlier this week, Rebecca shared a snap of her huge baby bump proving she was ready to pop at any minute, and yesterday morning (8 June), the Olympic gold medallist finally welcomed her daughter with husband Harry Needs.
Taking to Twitter, Rebecca announced the safe arrival of her new addition.
She tweeted: "@harryneeds and I are over the moon as we welcomed our beautiful baby girl this morning. She's doing well and we're so in love!!!"
Harry, meanwhile, took to his own Twitter page to tell followers welcoming his daughter was the "proudest day of his life".
He tweeted: "So sorry I've been so slack with replying to so many many lovely messages, but just wanted to thank everyone on the proudest day of my life."
"@BeckAdlington and baby needlington is doing so well," he added. "I don't know how many times they can bring a grown man to tears in one day."
In a final tweet, he gushed about wife Rebecca, writing: "Can't believe I feel in love all over again today. Thank you @BeckAdlington for making me the happiest man on this earth #daddysgirl."
So far, Rebecca and Harry have not yet revealed the name they have chosen for their newborn or any other details of her birth.
Their daughter is the couple's first child together and Harry joked he and Rebecca had been the most "impatient people" after waiting for their baby to arrive since Rebecca's due date last week, 4 June.
Fingers crossed we get to see a snap of Baby Adlington/Needs soon!
I'm A Celebrity star Rebecca first announced she was expecting back in December last year, revealing she couldn't wait to be a mum.
Her and Harry's baby joy came just three months after the pair tied the knot in a country wedding in Staffordshire.
Throughout her pregnancy, Rebecca had been keeping fans updated with plenty of baby bump pictures and in the final weeks leading up to her birth, she even gave fans a tour of the nursery she and Harry had put together for their baby.
It even included a decked out wardrobe with a first swimming costume for Rebecca's mini me. The first time mum gushed: "We can't wait to take her in the pool!"
Reckon she'll take after her mum by any chance?
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