The Mysterious Girl singer took to Instagram to show off his wife's unbelievable baking skills with several photos and videos of their son's cake.
"Theo is obsessed with windmills (no idea why) so Emily created this beauty. Happy birthday Theo. Love you so so much. Thanks @dr_emily_official," Peter captioned the post.
The delicious treat was decorated with green piped buttercream icing to create the appearance of grass, while chocolate Matchmakers lined the outside like a fence.
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Aside from the giant windmill, it also featured mini mushrooms and wildlife animals such as hedgehogs, chickens and ladybirds, while a stream ran through the middle of the pretty outdoor setting.
With the level of intricate detail, Emily's masterpiece wouldn't look out of place on the Great British Bake Off – and we predict it would even earn her a famous Paul Hollywood handshake!
Emily baked an incredible homemade cake to mark Theo's birthday
Peter's followers rushed to comment on the decadent creation, with one writing: "Emily that is incredible" and a second adding: "Wow boss cake, Happy Birthday." A third remarked: "Wow, this is amazing! How does she find the time to be a mum, a doctor and make creations like this? I need to up my game!"
This isn't the first time Emily has shown off her impressive culinary skills. Last year, the 31-year-old doctor celebrated Theo's third birthday with an incredible Toy Story-themed birthday cake while their six-year-old daughter Millie was treated to a colourful Smarties cake in January 2020.
Peter and Emily's son was treated to lots of presents
Another photo Peter shared on Saturday night gave fans a better look inside the birthday boy's celebrations, which included a huge rainbow-coloured balloon archway and a pile of presents stacked neatly on top of their dining room chairs.
It appears as though Peter and Emily marked the occasion at home with their two children Theo and Millie, as well as Junior and Princess, Peter's children with ex-wife Katie Price. All four kids and the former I'm a Celebrity star were huddled around the coffee table in their living room as they prepared for a night of board games.