carry a secret to (one's)/the grave

carry a secret to (one's)/the grave

To keep (not reveal) a secret for the duration of one's life. I can't believe that Grandma carried such a huge family secret to her grave! If Uncle Joe hadn't blurted it out, we'd never have known about it! Oh, Emily is a loyal friend—she would definitely carry a secret to the grave.
See also: carry, grave, secret
Farlex Dictionary of Idioms.

carry a secret to the grave

 and carry a secret to one's grave
Fig. to never reveal a secret, even to the day of one's death. John carried our secret to his grave. Trust me, I will carry your secret to the grave!
See also: carry, grave, secret
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • carry a secret to the grave
  • Graves
  • take a/the secret to (one's)/the grave
  • take the secret to the grave
  • the cat is out of the bag
  • won't breathe a word
  • not breathe a word
  • not breathe a word (of something)
  • in secret
  • mifky-pifky