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Cristina's freaked out moment is still the subject in the next "Grey's Anatomy". Meredith and Derek continue their efforts to ease Cristina back into surgery after her post-traumatic stress. The preview given shows that during a board meeting, Derek threatens to quit if Cristina is suspended.

The October 7 episode will also be a little crossover between the show and its spin-off "Private Practice". When Derek receives an unexpected and unwelcome visit from his estranged sister, Amelia, issues between the siblings - both past and present -- come to the surface. "Derek and Amelia witnessed a tragedy when they were young," Caterina Scorsone who plays Amelia told Fancast. "The murder of their father - and they dealt with it in very different ways."

"All we know on 'Private Practice' so far is that she had a prescription drug problem, and that she was in a very dark place and OD'd at one point," Scorsone continued. "But in the 'Grey's' crossover, we'll find out a lot more about what happened and why they feel so contentious with each other. We'll also find out a lot of back story about their dad, as well."

Meanwhile, the Chief tries to help Alex when he notices that he's refusing to use the elevators after his near-fatal shooting. Medically, Bailey is trying to convince a man who has a deformed hand to get a treatment.