The day we all sat up and took notice of Kate Middleton's littler sister was the very same day we asked ourselves: "How do I get a bum like that?"
Well now our question has been answered. Pippa has revealed the secret to achieving a pert bottom fit for any lady-in-waiting-wannabe.
For her latest column in Waitrose Magazine the near-royal was tasked with cooking French puddings for Valentine's Day with Michelin-starred chef Eric Chavot.
"Early morning - a tad too early, even for a military-fitness obsessive like me - and I'm in an underground kitchen in London's Mayfair sitting next to a gregarious Frenchman in shorts," she wrote.
Turns out cycling in a hot tub just wasn't quite enough gruelling exercise for Pips and now she keeps herself fit by training like she's in the army.
So if you want a butt like Pip's you need to get yourself down to a local park with British Military Fitness (BMF) where you'll be put through the pace with an exhausting training regime.
"You'll find that you push yourself and pull together with your classmates to take on the different activities and exercises that keep your classes interesting and invigorating," reads the BMF website.
"With the encouragement of your fitness instructor you'll train in pairs, in groups and teams, climbing over, crawling under and running around each other from the first to the last minute."
Grim. We're not sure about you but we'd just rather not.
LOVE PIPPA? See more from the duchess' sister here...
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