aunt vs nephew

aunt

noun
  • The female cousin or cousin-in-law of one’s parent. 

  • A woman of an older generation than oneself, especially a friend of one's parents, by means of fictive kin. 

  • The sister or sister-in-law of one’s parent. 

nephew

noun
  • A son of one's cousin or cousin-in-law 

  • A son of one's sibling, brother-in-law, or sister-in-law; either a son of one's brother (fraternal nephew) or a son of one's sister (sororal nephew). 

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