A boy waits to get vaccinated at an anti-polio campaign in Moradabad, India. Michaeleen Doucleff/NPR hide caption

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Indian schoolchildren wait in line for food at a government primary school in Hyderabad, India. Consistent access to nutritious food and clean water is key to helping children thrive, researchers say. Noah Seelam/AFP/Getty Images hide caption

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Researchers say intervention in early childhood may help the developing brain compensate by rewiring to work around the trouble spots. iStockphoto hide caption

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Garrett shares a moment with his mother, Natalie Peterson. "He has been doing so good," she says. "He's been smiling." Nicole Haley/University of Michigan Health System hide caption

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High school students whose friends posted photos of drinking and smoking were about 20 percent more likely to become drinkers or smokers themselves. iStockphoto hide caption

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While not conclusive, the two cases are "quite promising," says Anthony Fauci, a longtime AIDS researcher who directs the National Institute of Allergy and Infectious Diseases. Alex Wong/Getty Images hide caption

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