'Mysterious Girl' singer Peter, 43, shared the exciting news with fans via Twitter, uploading a scan picture alongside the caption: "OMG Dad to be AGAIN :)) Brilliant. So so happy."
Peter and Emily, 26, are already parents to daughter Amelia, two. He also has has son Junior, ten, and daughter Princess, eight, from his marriage to first wife Katie Price.
As you'd expect, loads of fans were quick to send their congratulations to the couple.
@MrPeterAndre aww congratulations to you and Emily so happy for you both— Lisall (@Xlisa18X) May 26, 2016
@MrPeterAndre congrats so happy for you both— LAURA (@lauramitchem1) May 26, 2016
@MrPeterAndre wooooooo exciting times ahead for u all xxx— Cheryl/'Charmer' (@chez89x) May 26, 2016
@MrPeterAndre congratulations x— Leanne loves joe (@stepsrule4eva) May 26, 2016
Peter has always been open about wanting to expand his family, telling Reveal in October last year: "We're not trying for another baby at the moment but a baby before next Christmas would really be something. I'd start right now, right this second. After this interview, of course.
"I wanted a boy before Amelia was born, but now we've had Amelia, she's the coolest baby and just so sweet, so I'd be happy with another girl."
Emily qualified as a doctor last year.
Congrats to Peter and Emily!
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