Get the Exclusive Details on the Grey’s Anatomy-Private Practice Crossover

If you haven’t yet heard, Grey’s Anatomy and Private Practice are doing another crossover this season, and TVGuide.com has the exclusive details on who’s popping up where.

Exclusive: Grey’s Anatomy and Private Practice doing another crossover

As we first reported, Private’s Amelia Shepherd (Caterina Scorsone) will venture up to Seattle Grace in the first hour of the crossover during Grey’s. She’ll plead with older brother Derek (Patrick Dempsey) and sister-in-law Lexie (Chyler Leigh) to help save the life of Erica (A.J. Langer), who, it was revealed in Thursday’s episode of Private, is suffering from a serious ailment.