leave alone vs stand in

leave alone

verb
  • To desist or refrain from involvement with. 

  • To stop bothering (a person). 

stand in

noun
  • A substitute; a replacement. 

verb
  • To substitute for; to replace; (theater) to serve as an understudy. 

  • To make one of a party in a bet or other speculation. 

  • To take a side in a dispute. 

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