There's nothing like a bit of sibling rivalry to spice things up a bit - and when it comes to the relationship between Prince William and Prince Harry, these two brothers have never been afraid of a little healthy competition.
So perhaps that was top of mind for William this week, when he decided to celebrate the anniversary of his younger brother's birth by providing Harry with a good old fashioned ribbing.
Well, as much ribbing as you can give when you're a royal and all….
Prince Harry celebrated his 36th birthday on Tuesday, September 15 in what appeared to be a very low-key manner.
The Prince is currently living in California, where he, wife Duchess Meghan and their one-year-old son Archie reside in their new Santa Barbara mansion.
The Sussexes have been in the US state since the beginning of lockdown, with the exact date of their next trip back to the UK still unclear.
But despite being unable to celebrate his special day with his UK-based family, the Duke was clearly feeling the birthday love going, by some of the special public messages he received - and William's was case in point.
In a picture posted on the official Instagram account of William and Kate, @KensingtonRoyal, a competitive Harry & Wills are seen running a race together with very, er, strained expressions on their faces.
"Wishing a very happy birthday to Prince Harry today!" the caption read.
The image paints a scene not unfamiliar to anyone with siblings - that smug feeling you get when you beat them at, well... anything is worth the pain.
Meanwhile, the Queen's official Instagram account, @TheRoyalFamily, also shared a candid pic of Harry from the archives.
In this one, the Prince is seen grinning widely at his regal grandmother the Queen.
The caption read: "Wishing The Duke of Sussex a very happy birthday!"
Explaining the origins of the picture, the post continued: "The Queen and The Duke during a Queen's Young Leaders reception at Buckingham Palace in 2017."
Harry's dad Prince Charles also shared a birthday wish on his and Camilla's Instagram page, @ClarenceHouse.
Two sweet images of Harry, one of them with Charles, accompanied the caption: "Wishing a very happy birthday to The Duke of Sussex today."
As a quick aside, if you ask us, we're firmly calling favourites in the Wills & Kate camp when it comes to picking peak birthday pics to show the birthday bloke some love.
Harry celebrated his birthday with another special addition.
In a statement, Harry and Meghan revealed they had donated AUD$176,000 to charity CAMFED, an African movement revolutionising how girls' education is delivered.
The incredible gesture came alongside a rare statement from the pair, where they explained their additional contribution came on top of the same amount already generated through fundraising efforts.
"No better way to celebrate what really matters. Thank you to everyone who donated, Harry and Meghan," they shared.
That's one very well rounded way to celebrate a birthday.