Maya Chamberlin, 4, needs a bone marrow transplant to treat a rare blood disease she was diagnosed with in September. Courtesy of the Chamberlin family hide caption

itoggle caption Courtesy of the Chamberlin family

Lisa Uncles, a certified nurse-midwife who's the acting clinical director of the Family Health and Birth Center in Washington, visits a new mother a day after she gave birth. Clients of the center have fewer premature births, low birth weights and cesarean sections as compared with the city's African-American population overall. Andrea Hsu/NPR hide caption

itoggle caption Andrea Hsu/NPR

Sam Kass, the assistant White House chef, picks spinach from the garden. Maggie Starbard/NPR hide caption

itoggle caption Maggie Starbard/NPR

Roberto Silva, 31, holds his 3-year-old son, Adil Noe Silva, at the CURE Orthopedic Pediatric Hospital in San Pedro Sula, Honduras. Adil has spina bifida, and the doctors straightened his legs so that hopefully he will be able to walk with braces on his legs. The nonprofit hospital treats children with bone deformities such as clubfeet, dislocated hips and fused fingers. Jason Beaubien/NPR hide caption

itoggle caption Jason Beaubien/NPR