disturb vs reassure

disturb

verb
  • to divert, redirect, or alter by disturbing. 

  • to confuse a quiet, constant state or a calm, continuous flow, in particular: thoughts, actions or liquids. 

  • to have a negative emotional impact; to cause emotional distress or confusion. 

reassure

verb
  • To reinsure. 

  • To assure anew; to restore confidence to; to free from fear or self-doubt. 

How often have the words disturb and reassure occurred in a corpus of books? (source: Google Ngram Viewer )