Possible Clues:

• Strangely timid ciao spoken like a native
• Foolish when keeping mum? That's colloquial!
• Silly to include mother in the vernacular
• Mother indulged in senseless sort of speech - that's characteristic
• Mother, I had ten with a twitch, in a manner of speaking
• Using characteristic speech
• Scholar translated into simple vernacular
• That''s what''s so silly about Mother, in a manner of speaking
• Like climbing the walls?
• It would be stupid if mother leaves, in a manner of speaking