pacify vs pester

pacify

verb
  • To appease (someone). 

  • To bring peace to (a place or situation), by ending war, fighting, violence, anger or agitation. 

pester

verb
  • To bother, harass, or annoy persistently. 

noun
  • A bother or nuisance. 

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