The ball of energy, who turns 25 today (Saturday 26 July), headed to London spot The Shard for a good old birthday yoga session.
Joined by her bestie and nutrition expert Madeleine Shaw, Millie busted some yoga moves while taking in the sights of the city from her impressive vantage point.
She said: "Yoga with a view @madeleine_shaw_ #theshard #yoga."
We love Millie's commitment to keeping fit!
But you'll also be pleased to know that Millie's birthday celebrations aren't ALL about stretches and downward dogs.
The former Made In Chelsea star shared a picture of her alcohol supplies for her birthday night.
So, quite a bit of booze for this lady, then!
Millie has been getting in to the birthday spirit for some time now, having been sent a beautiful bunch of flowers by her model agency.
On Friday, she said: "Thank you for my bday flowers @selectmodelmgmt @nikkitibbleswildatheart you are amazing!"
She also posted a throwback snap to her 21st birthday.
Along with her bestie, and fellow former Made In Chelsea star, Caggie Dunlop, Millie can be seen standing with a group of gal pals on a night out.
Millie added: "My 21st bday memories! @caggiesworld @florindacarey @madeleine_shaw_ @cbyclarissa"
Meanwhile, Millie's husband Professor Green let his caps lock do the talking, taking to Twitter on Saturday to
We hope you have a fab birthday, Millie!
Do you like to exercise on your birthday? Tell us below, as the best comment from across the website each week wins £50!
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