Robbie Williams and Ayda Field welcome 'very special secret' baby girl Coco

Robbie Williams and Ayda Field have welcomed a 'very special secret' baby girl via an 'incredible' surrogate.

The X Factor co-judges announced the arrival of Colette Josephine Williams, to be known as Coco, via Ayda's Instagram page on Friday morning, while detailing their 'long and difficult' path to a third child in a heartfelt post.

Sharing a black and white image of the family's hands in one frame, Ayda, 39, and Robbie, 44 - who are parents to daughter Teddy, five, and son Charlie, three - said they will be 'eternally grateful' to their surrogate.