In Zwilich’s third work for unaccompanied violin, the Pulitzer Prize-winning composer weaves a fabric of childlike melody together with sophisticated violin writing, providing a colorful and dramatic showcase for the soloist. Written for violinist Bella Hristova, whose father was a noted composer of children’s songs, the work draws inspiration from Zwilich’s memory of hearing the storybook “Gigi: The Story of a Merry-go-round Horse” read to her at age four. Still charmed by that memory more than 80 years later, “Gigi” is a reminder of the arts’ magical ability to keep the spark of childhood alive.