Royal fans can't believe this sweet detail from Prince Louis' birthday portrait

Don't fall out of your chair, but Prince Louis turns 7 years old today!

On 23 April, the Prince and Princess of Wales shared the most adorable portrait of their youngest child on Instagram to celebrate his big day — which is of course a beloved royal tradition.

This year, Louis' portrait was taken by photographer Josh Shinner, who has also shot Ashley Park, Emerald Fennell and Alexa Chung. Josh was also the artist behind Kate and William's family Christmas card photo in 2023.

The caption read simply: "Wishing Prince Louis a very Happy 7th Birthday!" with a birthday cake emoji.

The photo is as adorable as you'd expect, showing Louis sitting on a fallen tree trunk in a beautiful, flower-laden garden, wearing an olive green V-neck jumper over a checked shirt and a pair of dark-wash jeans.

But these details aren't what royal fans have glommed on to. Rather, commenters couldn't get over just how grown-up little Louis looks in the photo, and were also charmed by his sweet smile — which was missing a couple of front teeth. True to form, Louis cheekily smiled with his tongue poking ever so slightly through the gap. Oh, Louis.

"So grown up... At the stage of losing teeth," remarked one well-wisher.

"That smile! Me too I had this when I was seven," shared someone else.

"He’s so grown up! Happy birthday," wrote another.

Another said: "my goodness he has grown so much!"

It's true — it's hard to look at this grown-up little boy and picture the sassy four-year-old who stole our collective hearts when he made all sorts of funny faces during the Queen's Platinum Jubilee celebrations in 2022.

Meanwhile, Louis' sister Princess Charlotte will turn 10 (!!!) on 2 May, and his brother Prince George will turn 12 on on 22 July. Where has the time gone???