This Morning and Surprise Surprise presenter Holly, 33, told fans their exciting news this afternoon after posting a message on her website.
Holly and Dan already have a son and daughter and admit this little one is...a surprise!
"Surprise Surprise (and it was a surprise!!) I'm really happy and excited to tell you that Dan and I are expecting baby number 3!!" Holly wrote.
"We feel blessed and very lucky to be giving Belle and Harry a little brother or sister later this year."
Holly and Dan tied the knot in 2007 and welcomed their first child, Harry, in May 2009. Belle was born in April 2011.
Earlier this week, Holly was pictured leaving Celebrity Juice with a very large pink scarf draped right over her body. Now we know what she was hiding!
In November last year, Holly admitted in an interview with the Daily Express that she was feeling broody for a third child.
"I would like to have another one," she said. "If I'm lucky enough, but I don't know when. I'll just have to wait and see."
It's been a day of happy baby news in the celeb world. McFly's Tom Fletcher and his wife Giovanna announced the birth of their baby boy while Katie Piper also gave birth to her first baby, a girl called Belle Elizabeth.
Celebrities who have announced baby news in 2014:
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