It was announced on February 13, 2019, that Amy Acker had been cast as Derek Shepherd's fourth sister, Dr. Kathleen Shepherd. Acker is expected to appear in one episode this season, that episode being an Amelia Shepherd-centric episode.[1] On March 5, 2019, it was revealed that Abigail Spencer would reprise her role as Megan Hunt for one episode this season, which will air during Spring.[2]