Jessica Alba and Cash Warren are expecting their third child

Jessica Alba has revealed that she's expecting her third child with husband Cash Warren.

Actress Jessica shared a sweet announcement video featuring the couple's two daughters, Honor, nine, and Haven, five, to her Instagram account to confirm the lovely news.

'@cash_warren and I are officially going to be outnumbered #babyonboard #herewegoagain 👶🏼🤰🏽#blessed🙏' she wrote alongside the clip, where she's seen cradling her growing bump.

Hundreds of fans have taken to the comment section to express their congratulations to the pair, with one writing: 'Congrats to you and your family! My husband and I just had baby #5 and we love being outnumbered (lol) ... prayers for a healthy baby, pregnancy and delivery,' and another agreeing: 'Wonderful news!! Love the unique unveiling of Bub #3 ❤️'

Jessica and film producer Cash announced their engagement in 2007, after meeting whilst filming the Fantastic Four superhero franchise, and wed in a small courthouse ceremony in May of the following year.

Their first child, Honor, arrived in June 2008, followed by little sister Haven in August 2011. In 2012, Jessica also launched her business, The Honest Company, which supplies non-toxic, eco-friendly household products.

'It's incredible being a mum. I love it,' she said to Fabulous magazine of motherhood in September 2016.

'I was a lot more critical of my body [before having kids] when it was probably pretty awesome. I was so skinny! I was much more stressed and concerned about my body before I had kids. But now I know how silly and unimportant it is, so it's certainly given me perspective.'

She added that being pregnant had been an empowering experience for her in the past, explaining:'Being pregnant and giving birth gave me a new found respect for my body, it's amazing. It made me realise: "Oh right, this is why we have all the bits that we have!" There is a real reason for it.'