turn in his, her, etc. grave
turn (over) in (one's) grave
To (hypothetically) show enormous anger, disfavor, or regret for someone's actions or something that happens after one has died. That is, if someone were still alive, they would be greatly upset, angered, or disgusted by what has happened. I can't believe you're using our employees' pension payments to prop up a Ponzi scheme. The founder of this once-great company would be turning in his grave to see its directors stoop so low. Your poor mother would turn over in her grave if she heard the horrible things you were saying about your sister. I can't believe you wrecked your grandfather's prized truck. That's enough to make him turn over in his grave!
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
turn in his, her, etc. ˈgrave(British English) (American English roll in his, her, etc. ˈgrave) (of a person who is dead) likely to be very shocked or angry: Beethoven would turn in his grave if he could hear the way they’re playing his music.
Farlex Partner Idioms Dictionary © Farlex 2017