Most alt-country fans cite the harmonies of Gram Parsons and Emmylou Harris as the most gorgeous in memory. Harris and Parsons carried on a long tradition of high, close harmony singing created by the “family” bands of country music. From the Carter Family, to early brother duos like the Blue Sky Boys and the Delmore Brothers, brother and sister harmony is a foundation of folk and country music. Tonight Arty Hill, Caleb Stine, Claudia SanSoucie and Linda Nelson turn into a singing family for the night. Followed by a rare screening of the PBS documentary The Carter Family: Will the Circle Be Unbroken with interviews by Joan Baez, Rodney Crowell, Gillian Welch and others.