An overweight child reads her part during a skit that was in a 2010 program promoting healthy lifestyles sponsored by Children's Hospital near Denver. John Moore/Getty Images hide caption

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Ronan at 2 years old. "I know Ronan's purpose in life was to shed light on this disease," says his mother, Maya Thompson. "This is why I will continue to fight for childhood cancer for the rest of my life." Courtesy of Maya Thompson hide caption

itoggle caption Courtesy of Maya Thompson

According to a study published in Pediatrics, boys are entering puberty six months to two years earlier than they did in past studies. iStockphoto.com hide caption

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Jennie and Kristian Aspelin pose in a pumpkin patch with their children two weeks before three-month-old Johan died. Courtesy of the Aspelin family hide caption

itoggle caption Courtesy of the Aspelin family

People at a Denver party early this month celebrate the recognition of an amendment to the Colorado constitution legalizing recreational use of marijuana. Brennan Linsley/AP hide caption

itoggle caption Brennan Linsley/AP

The contents of a box of some of the new foods containing caffeine collected by the Center for Science in the Public Interest. Karen Castillo Farfán/NPR hide caption

itoggle caption Karen Castillo Farfán/NPR

There's new evidence that kids can reduce calories and feel full by snacking on veggies and cheese instead of chips. famfriendsfood/Flickr.com hide caption

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A boy in Lima, Peru, receives a hepatitis B vaccine during an immunization drive in 2008. The United Nations is considering a ban on the preservative thimerosal, which is often used in hepatitis B and other vaccines in developing countries. Martin Mejia/AP hide caption

itoggle caption Martin Mejia/AP