folks vs maternal aunt

folks

noun
  • The members of one's immediate family, especially one's parents 

  • People in general; everybody or anybody. 

  • The police. 

  • Late 19th and early 20th century migrants to California from Iowa and other parts of the Midwestern United States. 

maternal aunt

noun
  • A sister-in-law of one's mother; the wife or ex-wife of a maternal uncle. 

  • A sister of one's mother. 

  • A similar great aunt, etc. 

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