Possible Clues:

• Children drive the parents mad when they do this
• Of baby, having first gum growth
• Sprout canines
• Where to drive the mouthful you get this way
• Be angry with new leader and experience eruption, by gum!
• (Of baby) have gum pain
• Support article showing what babies do?
• Note Ethel, hiding what babies naturally do
• 'The way canines, for instance, come (6)'
• Get your teeth into it and prepare to drive to the end