baby of the family vs progeny

baby of the family

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

  • The youngest member of an immediate 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. 

progeny

noun
  • Offspring or descendants considered as a group. 

  • A result of a creative effort. 

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