little girls' room vs washhand-basin

little girls' room

noun
  • Synonym of ladies' room: a public lavatory intended for use by women. 

  • A room belonging to or used by little girls, particularly their bedroom. 

washhand-basin

noun
  • Synonym of washbasin 

How often have the words little girls' room and washhand-basin occurred in a corpus of books? (source: Google Ngram Viewer )