Jason Isbell and the 400 Unit's newest song, "Only Children," is a sparse, harmony-laden look back at a childhood relationship between "over-encouraged only children." Press play above to listen.

Driven by a quiet acoustic guitar and Isbell and bandmate and wife Amanda Shires' harmonies, "Only Children" focuses on two people who have shared intimate moments and a deep connection. Listeners get the sense the pair are both lonely: "Remember when we used to meet / The bottom of Mobile Street / Do what the broken people do?" Isbell sings.

The two are both dreamers, too, though: one a musician, one a writer. "You'd do whatever you put your mind to," Isbell sings; however, sadly, one of their lives ended early.

"Heaven's wasted on the dead / That's what your mama said / When the hearse was idling in the parking lot," goes the bridge. "She said you thought the world of me / And you were glad to see they finally let me be an astronaut."

Listen on repeat and the titular phrase morphs meaning: In one sense, the song's two protagonists are their parents' only children; in another, they're young, just kids.

"Only Children" comes from Isbell and the 400 Unit's forthcoming new album, Reunions. Due out on May 15, the 10-song project was produced by Dave Cobb and also includes the previously released "Be Afraid" and "What've I Done to Help."

Isbell's next record will be his first since 2017's The Nashville Sound. A No. 1 album on the Billboard Folk, Independent, Country and Rock Albums charts, that record received Best Americana Album at the Grammy Awards and Album of the Year at the Americana Honors & Awards. It was also nominated at the CMA Awards for Album of the Year, earning Isbell his first CMA nod.

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