The happy news was shared by Nathan, 27, via an Instagram video this morning, who called his wife a "hero".
Cara was rushed into hospital two days early for an induced labour after being diagnosed with preeclampsia -a pregnancy complication characterised by high blood pressure, usually beginning after 20 weeks.
Speaking from outside the hospital, Nathan said: "Just to let everyone know that Cara delivered our beautiful baby daughter this morning, she's done an absolute fantastic job. Cara you are a hero."
The baby girl is the couple's second child, after Cara, 29, gave birth to two-year-old Freddie in December 2017.
Nathan went on to say the morning had been "really emotional" but Cara and the baby are both doing well.
Over the weekend, Cara had posted a photo from her hospital bed writing: "Wonder how long we're going to be here."
Nathan added in the video: "I just want to say, us blokes could never in a million years go through what women do. So every woman who gives birth, hats off to you, could us geezers don't have the pain threshold."
He wrote in the caption: "Welcome to the world our little princess !!!! can't wait to spend our lives together !!! @cara_delahoyde your a legend, delivered our baby safe and sound !!! What a trooper you are !!! Hats off to all the pregnant women I salute you x"
Cara confirmed she was pregnant in March by sharing photos from an interview with New! Magazine, showing her husband holding her baby bump.
The couple met on the second series of Love Island in 2016 and went on to win the show.
A year later, they sadly announced they had split, however Cara discovered she was pregnant.
She told the The Sun at the time: "It's a shame and a sad situation. I know a lot of people will think, well you're going to have a baby together so just stay together - but we're not going to do that just to look like the perfect couple.
"Me and Nathan would always speak about kids, we said maybe when we're 30, but sometimes life doesn't go to plan."
The couple rekindled a few months later and welcomed Freddie in December 2017, before tying the knot in June 2019.
Featured Image Credit: @cara_delahoyde
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