Reminds me of when my family and I were in Tenerife airport recently. A brat started projectile screaming - not just normal prolonged crying but primal outbursts every 5 seconds. The parents seemed to think that this was perfectly acceptable. Of course, being mostly Brits we politely turned the other cheek. Not so an old French guy sitting nearby. He told the kid very loudly to STFU. It sounds much better in French. The kid and his parents understood French because he shut up pretty quickly.