The day before Diane Price's mastectomy, Jackson finally puts his foot down and says he won't do the surgery until Diane tells Maggie she has breast cancer. Reluctantly, Diane tells Maggie, who is stunned. She clearly feels betrayed they didn't tell her sooner, and walks out. Watch this scene from Season 13, Episode 17, 'Till I Hear It From You' and don't miss Grey's Anatomy THURSDAYS 8|7c on ABC.