family tree vs fathership

family tree

noun
  • The totality of someone's ancestors and offspring 

  • A diagrammatic representation of a pedigree, illustrating the connections between a person's ancestors, offspring and other relatives 

fathership

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

  • A title of respect addressed to a priest. 

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