On a gray, blustery November afternoon in Detroit, John Kish watches vigilantly as his four-year-old grandson, also named John, frolics on a towering play slide. If the day was sunny, there might be a line to use it, but given the weather, they have it to themselves. “It’s a long climb, but it gives them something to do,” Kish says, laughing, as the youngster carefully crosses a bridge within the structure.