As you'll see in the video above, Harry wagged his finger at six-year-old Alex Logan, who told ITV earlier this week that when he meets Harry he'll say, "I'm glad you've got your clothes on, Prince Harry".
So, at yesterday's London's WellChild Awards, the 27-year-old prince remembered to wear a suit and tie (the difference wearing clothes makes!) when meeting Alex, who has leukaemia, and other seriously ill children and their carers.
The youngster's mum Debbie recounted the moment Harry told her boy off.
"Harry said to Alex, 'You keep looking up at your mum, looks like you're dying to say something but you know she will tell you off'," Debbie told AFP.
"'I heard you were on ITV earlier, you said something cheeky, let's not talk about that here'."
But Dirty Harry, being the good sport he is, alluded to his recent bum-baring activities when starting his speech paying tribute to the inspirational children in the room.
"But never one to be shy in coming forward, I'll give it a go," Harry said to a laughing crowd.
Love your work, Hazza!
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