little boys' room vs washhand-basin

little boys' room

noun
  • Synonym of men's room: a public lavatory intended for use by men. 

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

washhand-basin

noun
  • Synonym of washbasin 

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