The blonde singer - who found fame on The X Factor - made a bit of a fashion boob with her white tee, which was decorated with a pair of lady lumps...
Hmmm... interesting choice of outfit there, Diana!
Clearly wanting her risqué tee to take centre stage, the starlet kept the rest of her look simple with a pair of black skinny jeans.
She also wore burgundy patent brogues and a tan leather handbag, completing her getup with bright animal print sunglasses (despite the fact there was no sun!)
Now, we're all for making a statement but we'd pick a cool slogan tee over a boob-clad one any day of the week...
Also attending the event was Kimberley Walsh, who upped the ante with a much more glamorous outfit.
The mother-to-be sported a super-tight pretty monochrome lace frock, leaving her growing baby bump on show for all to see!
What do you think of Diana's T-shirt? Let us know by commenting below as the best comment across the site each week wins £50!
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