get on someone's case
get on (one's) case
To start bothering someone about something. Oh, don't worry—I'll get on Pat's case until he agrees to go to the interview. It's too good an opportunity to pass up.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
get on someone’s case
in. to start harassing someone about a personal problem; to annoy someone. (Compare this with get off someone’s case.) I’ll get on Tom’s case about being late so much.
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.