Grey's Anatomy Season 9 will finally introduce another McDreamy sister, this time viewers will see the last one who hasn't appeared yet in the series.

Speaking to TV Line, Neve Campbell confirmed she is appearing soon on Grey's. But she could not reveal much about her story arc. She hints, however, that Derek (Patrick Dempsey)'s sister will visit Seattle in relation to his hand surgery.

In the last episode, Callie Torres blurts out to Derek that it does not feel right to declare he can't do surgeries again. They decide to explore more options.

Campbell starred with Dempsey in "Scream 3" in 1999. She described the actor to be "a great guy."

Asked what she thought of Grey's Anatomy, Campbell said: "They've been on that show for nine years and they definitely know what they're doing, so it was fun to be around a group that had been working together so long."

Campbell's multi-episode visit starts Dec. 6.

Grey's Anatomy on Twitter

Grey's fans shout out their thoughts on the ABC drama. Some of them tweet quotes that struck them the hardest.

"When you're feeling emotional... sometimes it's hard to keep a level head and consider all the facts." -Dr. Cristina Yang, Grey's Anatomy - wedyoung

Grey's Anatomy is a horrible show and you will fall in love with it and you will cry and you will have no life - ianthony314

Probably not cool that i watched so much Grey's Anatomy.... All kinds of ideas goin thru my head. Tumor,blood clot,head bleed,spine issue - IvyOutYoLeague

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