Credit: Video Still

On of the things we're most excited about on Grey's Anatomy Season 9, Episode 8: “Love Turns You Upside Down” (airing tonight, December 6) is the introduction of yet another one of Derek's (Patrick Dempsey) many sisters, Lizzie (Neve Campbell). Now, thanks to this sneak peek, we get our first good look at the newest Shepherd in town.

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It turns out Meredith (Ellen Pompeo) went behind Derek's back and had intern Heather (Tina Majorino) contact Derek's sisters to see if one of them would donate a nerve for Derek's surgery. Lizzie answered the call and, needless to say, Derek is not pleased.

Check it out below!

Credit: ABC Family © 2012 Disney ABC Television Group Photo: Grey's Anatomy Season 9, Episode 8 Sneak Peek: Meet Derek's Sister Lizzie (VIDEO)

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Catch the next new episode of Grey’s Anatomy on Thursday, December 6 at 9 p.m. ET/PT on ABC.

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