She doesn't stand as one of the best characters it's just the opposite because she's been on the list with the 20 unpleasant characters like Tom Barrow and O'brien. As a matter of fact, Mary was mean particularly to her sister mother father grandmother and Carson.

Mary wasn't one of the beloved characters in Downtown Abbey. She was one of the 20 mean characters because she was kinda mean to many people with her nasty reactions and responses