Peter has spent the day with Cancer Research UK and decided to dress up for the occasion in a fun and fluffy onesie.
Posing for a photograph, the Aussie looked hard a work as he sat with paper and pen in his baby blue unicorn costume.
Commenting on the picture, which has been posted on Twitter, Peter: "Onesie at work day. Launching my #PetesChampions campaign in style today with @CR_UK :))."
Last year, Peter unveiled his Pete's Champions initiative, which is made up of an army of supporters who fundraise and spread the word about detecting cancer early.
It came following the sad death of Peter's older brother Andrew, who passed away following a battle with cancer in December 2012.
Today, Peter was chairing a Twitter takeover for Pete's Champions and he had previously tweeted: "Got a question about how to raise money for the #PeterAndreFund? Then join me tomorrow when I take over @CR_UK's Twitter."
Good work, Pete!
For more info about Pete's Champions, click here.
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