The rapper even filmed a short video of Millie after she had dropped off in the back of a taxi, and posted it on his Instagram page.
Scroll down to watch. As you can see, Millie looks kind of surprised to wake up and find a camera in her face!
Pro added: "Oh dear, the narcoleptic is at it again."
Millie retorted: "Sorry I can't seem to stay awake in your company #narcoleptic #thishastostop"
She also re-tweeted a follower who pointed out: "I would forever be living in fear of falling asleep if i was poor @millsmackintosh."
It's not the first time Pro Green has snapped his wife catching forty winks, either.
Earlier in May, he papped her asleep in the back of yet another car, adding: "Should probably wake her up before she gets neck ache."
Sort it out, Pro!
Here's the evidence...
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