fathership vs paternity

fathership

noun
  • The state of being a father; fatherhood; paternity. 

  • A title of respect addressed to a priest. 

paternity

noun
  • fatherhood, being a father 

  • legal acknowledgement of a man's fatherhood of a child 

  • authorship 

  • parental descent from a father 

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