baby doll vs lovebug

baby doll

noun
  • A young attractive woman; sweetheart, darling. 

  • A style of women's nightdress. 

  • A child's doll designed to look like a baby. 

lovebug

noun
  • A person who is in love; a sweetheart. 

  • An insect, the honeymoon fly (Plecia nearctica, family Biblionidae). 

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