It was recently announced that Neve Campbell will guest star in an upcoming episode of Grey's Anatomy as one of Derek’s (Patrick Dempsey) sisters. Since Derek has four sisters, and we already know one of them quite well (Amelia Shepherd, played by Caterina Scorsone on Private Practice), which one do you think Neve will play?

We should also note that we’ve met another one of Derek’s sisters before in Season 3, Episode 6: “Let the Angels Commit”: Nancy Shepherd (played by Embeth Davidtz), who is an OB/GYN in Connecticut. Nicknamed McBitchy by fans, Nancy never liked Meredith (Ellen Pompeo), and preferred Addison for Derek. Thankfully, Derek didn’t listen to her advice.

Also mentioned in “Let the Angels Commit” was Kathleen Shepherd, one of Derek’s sisters who we’ve never met before. In the episode, Kathleen was supposedly worried about Derek because he’d stopped coming home regularly to visit his large family on the East Coast. So Kathleen sent Nancy to check in on him. Kathleen is also a doctor, working as a psychiatrist.

Then there is the fourth, unnamed sister, who we’ve learned very little about, aside from the fact that she exists. Since Derek has nine nieces and five nephews, we’re guessing that Neve’s character will have a kid or two.

Clearly, Neve will be playing either Kathleen or the unknown sister. Our bet is on Kathleen, since we already have a little background on her, and also because it will be fun to have a psychiatrist around. We wouldn’t be surprised if she was called in to treat some of the plane crash survivors. And, hopefully, bring some of Zola’s cousins with her to play with!

Which sister do you think Neve will be playing? Tell us in the comments!

Catch the next new episode of Grey’s Anatomy on Thursday, October 18 at 9 p.m. ET/PT on ABC.

Molly Friedman is an editor at Wetpaint Entertainment. Follow her on Twitter @MollyFriedman.

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