Researchers at Children’s Hospital of Philadelphia have been following and studying the brains and lives of so-called “crack babies” for more than 20 years. Now, they’re beginning to publish their findings, and what they’re finding is not what they expected. The researchers saw few statistical differences between kids exposed to crack in utero and those who weren’t. But they did find big differences between the exposed babies and the controls when compared to children who grew up in wealthier families. Now, they’re coming to the conclusion that it’s poverty — not crack — that may present the biggest risk to children’s neurological development and their later opportunities in life.