dare vs have someone's back

dare

verb
  • To have enough courage to meet or do something, go somewhere, etc.; to face up to 

  • To terrify; to daunt. 

  • To have enough courage (to do something). 

  • To catch (larks) by producing terror through the use of mirrors, scarlet cloth, a hawk, etc., so that they lie still till a net is thrown over them. 

  • To defy or challenge (someone to do something) 

noun
  • The quality of daring; venturesomeness; boldness. 

  • A challenge to prove courage. 

  • In the game truth or dare, the choice to perform a dare set by the other players. 

  • A small fish, the dace 

  • Defiance; challenge. 

have someone's back

verb
  • To be prepared and willing to support or defend someone. 

How often have the words dare and have someone's back occurred in a corpus of books? (source: Google Ngram Viewer )