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TV Nostalgia

How Can You Tell Mary-Kate and Ashley Olsen Apart?

Someone do a DNA test, because Mary-Kate and Ashley Olsen are supposedly fraternal — aka, not identical — twins. Madness. (That means their song “Identical Twins” off their hit record, Brother For Sale, was a lie.)

These birthday girls, who turn 28 this Sunday, July 13, certainly look enough alike to pass for each other, and we have a hard time telling who is who. After some scientific calculations; many years of watching Full House, Passport to Paris, and So Little Time; and a little help from this video, we think we may have cracked the code on how to tell the Olsen twins apart.

Check their hands.

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Mary-Kate is left-handed; Ashley is right-handed. If you see a twin holding a gargantuan coffee in her left hand, it’s likely MK.

Find a freckle.

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It’s often hard to see, but if you’re watching reruns of Full House, you might spot the tiny freckle Ashley has under her nose. According to her, it disappeared when she got older.

Gaze into their eyes.

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Ashley’s peepers pop, while Mary-Kate’s aren’t quite as wide.

The nose knows.

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It can be hard to bust out the eyeball trick if MK and Ash have donned sunglasses, as they so often do. Fortunately for us, Mary-Kate has a slightly slimmer nose than Ashley.

Measure the difference.

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Ashley is taller. By less than an inch, but still.

Browse their brows.

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This mostly helps the twins are side-by-side, as both girls keep their brows pretty well groomed, but Mary-Kate keeps her brows a bit thinner.

Do a fashion check.

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The designers have different styles. While Ashley opts for more simple, feminine ensembles, Mary-Kate piles on the accessories and often wears darker colors, for a slightly edgier look.

Look at the lips.

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Both twins enjoy making the duck lips, but MK does it more. So if you see one of them doing it, it's a 75% chance it's Mary-Kate. Plus, Ashley has more pillow-y bottom lip.

This article is an update of a previous feature by Jenny McGrath. Follow her on Google+!