Greys Anatomy - Season 12 -

: Meredith Grey adjusts to life as a widow, moving back into her mother's house with her "sisters," Maggie Pierce and Amelia Shepherd. A major mid-season arc involves Meredith being brutally attacked by a patient, leading to a long recovery and therapy.

: Tension peaks when Callie’s new girlfriend, Penny, is revealed to be one of the doctors who failed to save Derek. Penny eventually joins the hospital as a resident, causing friction with Meredith and Amelia. Relationship Turmoil : Greys Anatomy - Season 12

: The couple's marriage collapses, leading to a divorce. However, they discover April is pregnant shortly before signing the papers. : Meredith Grey adjusts to life as a

: Jason George (Ben Warren) was promoted to a series regular. Giacomo Gianniotti (Andrew DeLuca) also became a regular mid-season. Penny eventually joins the hospital as a resident,

: A bitter custody battle over their daughter, Sofia, ensues when Callie plans to move to New York with Penny.