make nice vs mitigate

make nice

verb
  • To be friendly or conciliatory towards another, often in the context of maintaining good relations or resolving a conflict with the other person. 

mitigate

verb
  • To reduce, lessen, or decrease; to make less severe or easier to bear. 

  • To downplay. 

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