bred in the bone

bred in the bone  {adj. phr.}

Belonging to your nature or character, especially from early teaching or long habit; natural from belief or habit; believing deeply.

The Willett children's cleanness is bred in the none.

Often used, with hyphens before the noun.

Joe is a bred-in-the-bone horseman; he has been riding since he was six.

Contrast: SKIN-DEEP.