In 1940, Belpré met her future husband, the African-American composer and violinist, Clarence Cameron White. They were married on December 26, 1943 and Belpré resigned her position to go on tour with her husband and to devote herself fully to writing. When her husband died in 1960, Belpré returned to part-time work in the library as the Spanish Children's Specialist, which sent her all over the city wherever there were large numbers of Latino children. In 1968, she retired from this position, but was persuaded to work with the newly established South Bronx Library Project, a community outreach program to promote library use and to provide needed services to Latino neighborhoods throughout the Bronx.