The Duchess of Cambridge is playing hostess and plans to whip up a feast of beef Wellington and fish pie for 30 of Harry's closest pals.
Not only is Kate also doing his favourite pudding (Eton mess), but she's got Pippa making the cocktails.
Now we all know that Prince Harry loves to party and the signature birthday boy beverages - "MacDonald Windsors" and "King's Ginger Cocktails" - are sure to go down a storm.
The question is, what do you buy a prince for such a milestone birthday? Let's not forget that Prince William was gifted a cool £8 million helicopter by the Queen for his 32nd in June.
While Harry has asked for donations to be made to charity instead of any presents, he has made a little request. Think four-legged and Andrex soft.
"Harry wants a labrador puppy and that's what he has asked for," says a royal source.
Prince Harry with a super-cute labrador in his arms? As if he doesn't get enough attention already.
*Please* say he gets his birthday wish. Plus, just imagine Prince George's face when he sees he's got a puppy playmate - let's just hope Kate and Wills' pet dog Lupo isn't too put out.
LOVE PRINCE HARRY? Take a look through this gallery to see more photos of the birthday boy to-be.
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