extended family vs sept

extended family

noun
  • A family consisting of parents and children, along with additional members such as grandparents, grandchildren, aunts or uncles, cousins, etc. 

sept

noun
  • A clan, tribe, or family, proceeding from a common progenitor; especially, one of the ancient clans of Ireland. 

  • An enclosure; a railing. 

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