After saying farewell to Sandra Oh and writing out two other characters in its recently concluded 10th season, ABC's Grey's Anatomy is starting to bulk up.

Caterina Scorsone has been promoted to series regulars for the 11th season of the Shonda Rhimes medical drama, The Hollywood Reporter has learned.

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Scorsone returned to reprise her Private Practice role as Dr. Amelia Shepherd — Derek's youngest sister — in May and recurred throughout the remainder of season 10. The neurosurgeon helped sister-in-law Meredith (Ellen Pompeo) around the hospital and provided surgical support at Grey Sloan Memorial while Derek (Patrick Dempsey) was in Washington. She first boarded Rhimes and Betsy Beers' Grey's Anatomy spinoff Private Practice as a recurring player in season three and was promoted to regular in season four, where she crossed over to Grey's for two episodes in 2010 and 2012. Scorsone is repped by Innovative and Open Entertainment.

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Scorsone boards the series after Grey's said farewell to Oh's Cristina Yang as well as Gaius Charles' Shane — both of whom moved to Zurich — as well as Tessa Ferrer, whose character was fired from the hospital. She joins a cast that includes Pompeo, Dempsey, Chandra Wilson, James Pickens Jr., Sara Ramirez and Justin Chambers — all of whom inked new two-year deals to return to the medical drama — as well as Kevin McKidd, Jessica Capshaw, Sarah Drew, Jesse Williams, Jerrika Hinton and Camilla Luddington.

Grey's returns to ABC this fall in its new home on Thursdays at 8 p.m.

Email: Lesley.Goldberg@THR.com

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