A fight over whether Taipei mayor Chiang Wan-an's teenage son got special treatment to study in the US is heating up the city's election race, and it is turning into a headache for Chiang.

• Chiang's eldest son won one of 25 spots in a city-funded international exchange program and left his Taipei high school to go to the US.
• Critics say the real issue is whether Chiang properly stepped back from a program his own city government runs, not the boy's ability.
• Puma Shen, Chiang's DPP rival for mayor, says fake accounts and false claims are dragging the child into the fight, which he calls unacceptable.
• Chiang is pushing back hard, saying attacks should target him and not a minor, and he brushed off a call from a former UMC chairman to resign.
• Some DPP lawmakers worry the attacks are overdone and could backfire on their own side.

Outlook: With candidate registration closed, expect the privilege row to keep running as a central theme of the Taipei mayoral contest.