Possible Clues:

• Duel (with)
• Come into conflict (with)
• In efforts like this, sons take part in quarrel
• Puzzles about saint engendering fight
• Argue with solver initially taken in by puzzles?
• Fight follows angry exchange about school head
• Angry exchanges, then second interrupts to start the duelling
• Get into a dispute
• Angry, angry talk about Pole entering dispute
• Argue as son interrupts this hobby