Exploring the musical ties that bind, we spin platters from our favorite harmonizing pairs and family affairs. We map the careers of West Texas-troubadour Jimmie Dale Gilmore of the Flatlanders and So-Cal rocker Dave Alvin of the Blasters and trace the events that led to their cosmic collaboration. And we follow the journey of funk singer Syl Johnson and blues guitarist Jimmy Johnson from Mississippi to Chicago, and the different paths the sibling rivals carved out in the Windy City’s electric soundscape. Plus, country duets and family bands. Soul sisters and blues brothers. Lovers, kindred spirits, and lots of others.

This holiday weekend American Routes boogies down to bayou country to catch live music at Festival International, a showcase of French music from southwest Louisiana and the wider Francophone world along with blues, Chicano nouveau and swamp pop. For the 31st annual festival, we hear female Cajun supergroup Bonsoir, Catin tear up the stage; bluesman Corey Harris ring out the Mississippi Delta’s West African roots; and blue-eyed soul from swamp pop legends Johnnie Allan, T.K. Hulin, and G.G. Shinn. Plus, accordionist CJ Chenier, son of Clifton Chenier, proves he is carrying on the king of zydeco’s royal bloodline. Las Cafeteras from East Los Angeles give us a taste of Veracruz’s Afro-Latin jarocho music, including the folk-turned-pop song “La Bamba.” And Texas singer, fiddler, and accordionist Cedric Watson adds Caribbean and Latin flavors to his homegrown Creole sound.