Pete, 43, confirmed the exciting news on Tuesday evening (22 November), saying that 27-year-old Emily had given birth to a boy.
Taking to Twitter, he gushed: "Very very happy for our new baby boy :))"
Peter has not revealed any further details about their new baby, however he has been inundated with well-wishes from fans.
One tweeted: "Sending you both and the rest of your family the BIGGEST of congratulations!" Another added: "Made up for you both!"
Peter has since tweeted: "Thanks so much for all your lovely comments. Buzzing."
Meanwhile, his spokesperson told The Sun: "Peter and Emily are both extremely happy. Both mother and baby are doing fine."
Australian singer Peter and doctor Emily are already parents to two-year-old daughter Amelia. Peter also has two children, Princess and Junior, from his previous marriage to Katie Price.
The couple announced Emily's pregnancy in May.
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