baby of the family vs bairn

baby of the family

noun
  • The youngest member of an immediate family. 

  • A member of an immediate family who behaves as, or is treated as though they were the youngest member of a family. 

  • An adult member of an immediate family who is treated by others in the family, especially the parents, as though they were a child. 

bairn

noun
  • A child or baby. 

verb
  • To make pregnant. 

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