Pop icon Robbie Williams and his wife Ayda Field have delighted their fans with a surprise, announcing the birth of their third child, a daughter born via a surrogate.

Upcoming ‘X Factor’ judge Field shared an image via Instagram of her family’s hands, including those of their brand new baby, on Friday morning (September 7th).

In a lengthy caption, the couple – who are already parents to five year old daughter Theodora Rose and three year old son Charlton – revealed their “long and difficult path” to welcome their third baby via an “incredible” surrogate.

“So we have been keeping a very special secret! We are delighted to share with you that we have had a baby girl… welcome to the world Colette (Coco) Josephine Williams!!” the American-born actress wrote.

“It has been a very long and difficult path to get here, which is why we have kept it on the down low. Family comes in all forms, and this little lady, who is biologically ours, was carried by an incredible surrogate mother, to whom we will be eternally grateful.”

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“As with Teddy and Charlie, we ask that you respect Coco's privacy and allow us to grow into our new team of 5! #TeamWilliams,” she finished her post.

The couple’s third child arrives just a few weeks before they’re both due to be involved with the 2018 series of ‘The X Factor’ on the judging panel, alongside Simon Cowell and fellow newcomer Louis Tomlinson of One Direction. Sharon Osbourne is due to be the first-ever fifth judge, but only on the series’ live shows.

Before the series started last weekend, Field told a press conference: “I think for me, on a professional level, I've auditioned for years… I know what it's like to have the stakes high. To put it all out there. I think being with Rob for 12 years… I've been every step of the way with him. I have a huge amount of empathy for the process. I know what it takes from creating the songs… to promoting, to live shows. It's a very emotional process.”

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