be a party to vs sip

be a party to

sip

noun
  • A small mouthful of drink 

verb
  • To drink slowly, small mouthfuls at a time. 

  • To drink a small quantity. 

  • To taste the liquor of; to drink out of. 

  • To consume slowly. 

How often have the words be a party to and sip occurred in a corpus of books? (source: Google Ngram Viewer )