The rapper made sure he pulled out all the stops for his girlfriend as he jetted her off to New York for a surprise trip.
Millie has already said on Twitter that it was 'the best birthday ever', and we are so glad she had such a fab day.
However, it seems her boyf was slightly concerned for the purse string. Just before they were about to leave the rapper tweeted:
"About to board. #NYC. #Shopping. #Anightmareformypocket. #mightbearenegadeandnotdrawthecurtainsinourroomatthestandard."
[Related story: Professor Green has a Millie-related Twitter rant]
[Related article: Professor Green and Millie Mackintosh forced to separate?]
We're not sure what that last bit means, but suspect it might be rude.
For those who's eyes are tired or can't be bothered, it reads 'might be a renegade and not draw the curtains in our room at the the standard'.
He later deleted the tweet so maybe we are right?
Cryptic messages aside, despite both the stars tweeting where they were off to, Pro Green was not too chuffed to see the paparazzi waiting for the pair in the arrivals lounge.
He tweeted: "Paps in NY. Brilliant, just what you need after an ambien."
Plus, it looks like he might be experiencing some bad karma after he later wrote:
"Tornado warnings in NY and from the window it looks like the root of it is the Empire State Building. Insane."
Eek. We hope they are OK! We are sure Millie will find some shops to seek shelter in! Pro Green's wallet better watch out.
And it sounds like they are having a great trip thus far, with P.Green later reporting:
"Met some brilliant Scotsman earlier @The Standard then got suitably wasted before an incredible meal @ Morimoto. Goodnight."
Wasted before dinner? We're not sure we could handle things in that order. But then again, he is well hard and from Hackney after all. We just hope Mills can keep up!