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Emma Watson mistaken for child traveling alone at airport

Ian Gavan / Getty Images file

Emma Watson.

In Hollywood, a youthful look is an asset. In the line at airport security, not so much.

It's a lesson Emma Watson found out the hard, somewhat embarrassing way, as the erstwhile "Harry Potter" star took to Twitter to reveal that a member of the TSA held up her recent holiday journey after being convinced that she was a child.

Make that, a very young child, in need of a parent to travel with.

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"Passport control: 'unaccompanied minor?' Me: 'sorry?' Passport control: 'where is ur guardian?' Me: 'I'm 22!!!!!!! #neverwearingabackpackagain."

Clearly, that particular agent wasn't a Hermione fan. Well, at least the Brit -- proving she's ever bit an adult on the current cover of Marie Claire, incidentally -- has a sense of humor about it.

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Then again, she's had some practice, as it's not exactly an unusual occurrence.

"The really sad thing is that this is not the first time this has happened," she added.

Long live the youthful glow.

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