Cities that stress their “coolness” to draw new residents and stimulate development are falling behind their family-friendly counterparts. That’s according to an analysis of migration data by the Praxis Strategy Group, as reported in a Nov. 27 Wall Street Journal guest column. Why are packed playgrounds a surer sign of business growth than crowded singles bars? Because married people with children “tend to be both successful and motivated, precisely the people who make economies go,” writes Joel Kotkin, author of The City: A Global History. “It’s time to recognize that today, as has been the case for millennia, families provide the most reliable foundation for successful economies.”