pester vs ruffle some feathers

pester

verb
  • To bother, harass, or annoy persistently. 

noun
  • A bother or nuisance. 

ruffle some feathers

verb
  • To cause a disturbance; to arouse resentment, anger, or concern. 

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