Questions or suggestions? E-mail Maria.DiMento@Philanthropy.com

Development: Derek Lieu

Reporting: Maria Di Mento, Caroline Preston, and Sarah Frostenson

Data: Emily Gipple

Photo research: Sue Lalumia and Emma Carew-Grovum

Photo credits:

Kin Cheung/AP Images, Dave M. Benett/Getty Images, Laura Burlton, Marty Lederhandler/AP Images, Mario Tama/Getty Images, Mark Washburn Photography, Kevork Djansezian/Getty Images, Krista Kennell/Sipa Press/Newscom, Mark Lennihan/AP Images, Lane Hickenbottom/Reuters/Newscom, McMullan Co/SIPA/Newscom, Mary Knox Merrill/Northeastern University, Gregg DeGuire/WireImage/Getty Images, Matt Cardy/Getty Images Europe, Paul A. Hebert/FilmMagic/Getty Images, David Duprey/AP Images, Anila Preston/Help a Child Trust Foundation, Monie Photography, Columbia University Medical Center, Sylvain Gaboury/PatrickMcMullan.com/SIPA/AP Images, Stephen Lovekin/Getty Images, Astrid Stawiarz/Getty Images, Fred R. Conrad/The New York Times/Redux, Peter Foley/Bloomberg/Getty Images, Mark Beane, Loyola University Chicago, Claremont McKenna College, Matt McClain/Washington Post/Getty Images, Michael Murdock/Splash News/Newscom, Jurek Wajdowicz/EWS, Barcroft Media/Landov, Scott Eells/Bloomberg/Getty Images