'Grey's Anatomy' Postmortem: Patrick Dempsey Teases Shepherd Family Drama Ahead

"Grey's Anatomy's" Patrick Dempsey and Ellen Pompeo

[Warning: This story contains spoilers from Thursday's "Love Turns You Upside Down" episode of Grey's Anatomy.]

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Talk about awkward family reunions.

During Thursday's Grey's Anatomy, Meredith went behind Derek's back -- with the help of intern Heather -- in an attempt to help repair the nerve damage to her husband's hand in a bid to salvage his surgical career.

Heather (Tina Majorino), despite Derek's demand that she reach back out to his four sisters, his previously unseen sibling Lizzie (Neve Campbell) arrives in the final moments of the hour.

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"She's coming up [to Seattle] about Derek's hand and to find out what's really going on," Patrick Dempsey told The Hollywood Reporter during a recent visit to the medical drama's Hollywood set. "Shepherd has been withholding any information with the family and she questions why he's not opening up."

Lizzie arrives much to Derek's chagrin but it will be Meredith (Ellen Pompeo) who will bare the brunt of her wrath after she's been left out of the big events of the couple's life. 

"My feeling is that Derek's always trying to protect them and because of that there's a sense of resentment," Dempsey says. "It's Meredith's fear of losing the baby, that's what's driving her. Derek's been overprotective."

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And Lizzie couldn't come at a more opportune time as Meredith has just told Derek that she's pregnant -- news that considering her pervious miscarriage, she wants to keep under wraps.

"The dynamic is, 'Why are you not telling us what's going on with your family -- and you're married and you have kids; you should be letting our family into yours,'" Dempsey adds.

With the surgery looming, Derek is clearly nervous about the procedure -- which may or may not include the nerve that brings Lizzie to town -- and how it will impact his career, which this season has been unsatisfyingly spent teaching.

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"Derek is scared about going into surgery again and the choices that he has are not choices that are going to make a difference; they're going to hurt him more than they're going to help and his anxiety is coming from that," Dempsey says.

"With the loss of his ability to operate now, he's coming to terms with what he's going to do with his life and teaching is certainly not going to be the answer," he adds. "He's not finding any joy in that because he can't go in and the way he teaches is to demonstrate and you can't demonstrate unless you're in the OR."

Meredith's surprise pregnancy, Dempsey notes, was a "nice turn" for the couple and something he didn't see coming. "Derek is much more optimistic about it than she is and very supportive," he says. "She is very nervous about losing the child again and her conflict is much more about, 'Will we have a full term and will she have the baby?' "

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The combination of Derek's anxiety about his hand and Meredith's pregnancy creates quite a dilemma for Zola's father as he confronts his future.

"He's willing to drop out and be at home with the baby and raise the child, but at the same time, he's being pulled to confront his anxiety and fear about going into surgery again and finding a procedure that's going to work to allow him to get back into the OR," Dempsey says of the surgery that Callie (Sara Ramirez), Jackson (Jesse Williams) and intern Shane (Gaius Charles) will oversee.

As for the family matters at hand, Dempsey says he'd love to see his former Scream 3 co-star Campbell return. "We just get a little glimpse of her and her dynamic but it'd be fun to have Neve come back as a regular."

Do you think Derek will return to the OR? Hit the comments with your thoughts. Grey's Anatomy airs Thursdays at 9 p.m. on ABC.

Email: Lesley.Goldberg@thr.com; Twitter: @Snoodit