The Olsen twins are a talented duo...
And have been in front of the snappers since they were wee.
But over the years there is one thing we can't help but notice - time after time.
These ladies would give Keira "pouty" Knightley a run for her money when it comes to lip-curling for the the snappers.
It seems all they need is the whiff of a pap and it's cheeks in and lips out.
But while it can't be denied that both girlies employ the pucker, we're keen to know which one looks the best doing so.
We reckon a little sibling rivalry is healthy.
And with that in mind we've pitted the chicas against one another.
Check out their lip-pushing skills in our gallery of Mary-Kate and Ashley Olsen: the pout-off - believe us, the results may surprise you.
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