boetie vs bub

boetie

noun
  • brother 

  • man, fellow 

bub

noun
  • A young brother; a little boy; a familiar term of address for a small boy. 

  • A term of familiar address; bubba; bubby. 

  • A woman's breast. 

  • A baby. 

  • An alcoholic malt liquor, especially beer. 

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