Earlier today, Peter announced his and Emily's happy news by sharing a scan picture with his followers on social media.
The couple already have one child together, two-year-old Amelia, and Pete couldn't contain his excitement as he gushed: "OMG Dad to be AGAIN :)) Brilliant. So so happy."
After their announcement, Peter and Emily headed into central London before attending a special event at Buckingham Palace. The garden party was in aid of The Not Forgotten Association, which is a charity that supports all injured service men and women of all ages.
Peter and Emily dressed perfectly for the occasion, but sadly it seems it is still a little early to catch a glimpse of a baby bump!
While Australian singer Peter looked dapper in a white shirt and black suit, Emily opted for a smart white pencil skirt and stripped blouse. The doctor wore her long hair in a low ponytail and looked pretty radiant for the second trimester of pregnancy!
The couple were pictured holding hands in the Palace grounds, and Peter has now shared the photograph on Instagram. Writing alongside it, he said: "What an amazing day at Buckingham Palace for The Not Forgotten Association. Met some true heroes :)"
Peter has spoken a lot 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."
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