Cindy Lou WHO? The celebrity you didn't know played your favorite Whoville resident

Christmas spirit swept the nation in 2000 when Cindy Lou Who more than doubled the size of our favorite Christmas villain's heart in 'How the Grinch Stole Christmas'. With a kind soul and an interesting hairdo, to say the least, Cindy Lou Who became a holiday icon.

So it might surprise you that just seven years later, the actress who portrayed Cindy showed up in New York City's Upper East Side -- a long way's away from Whoville. That's right, folks, Cindy Lou Who and little Jenny Humphrey from 'Gossip Girl' have one huge thing in common -- they're both played by Taylor Momsen.

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In case your memory needed some jogging (story continues below):

As if it were an extension of her 'Grinch' character, Jenny Humphrey was the sweet but naive little sister of Dan, Serena's eternal flame. And although she started out as everyone's little sister, she eventually transitioned into a rebellious, tough cookie determined to take down queen bee Blair Waldorf.

Look back at Momsen throughout her career:

Seemingly living a life parallel to her on-screen personas, Momsen went through quite a transition herself, especially when compared to the sweet Who that convinced the Grinch to return all the Christmas presents he stole. In 2009 she joined an "aggressive rock & roll" band called The Pretty Reckless who produced an album called 'Going to Hell', including songs with names like 'Make Me Wanna Die' and 'F**ked Up World'. You get the picture.

Momsen aptly adopted a punk-rock countenance to match her grungy music -- rarely seen without intensely dark eye makeup, platinum blonde hair and ivory skin, the former gossip girl totally rocks the bad girl look.

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Forever friends

A post shared by Taylor Momsen (@taylormomsen) on Jan 11, 2015 at 2:31pm PST

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A post shared by Taylor Momsen (@taylormomsen) on Mar 9, 2015 at 7:18pm PDT

So, if you've been wondering for 15 years, Cindy Lou WHO?, your question is finally answered: Taylor Momsen.

Xoxo, Cindy Lou.

In case you weren't convinced that Momsen is no longer the little girl from 'How the Grinch Stole Christmas':

Taylor Momsen Hints at Playboy Pictorial
Taylor Momsen Hints at Playboy Pictorial

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