WHEN most families fight, as most families do, you might hear about it over the back fence or see a stray post on Facebook. When the Wainwrights get into it, the spat often shows up in a full-blown song, which begets other songs. That kind of thing will happen when one of America’s most bracing folk writers, Loudon Wainwright III, marries another folk luminary, Kate McGarrigle of the McGarrigle Sisters, and they have two musically gifted children, Rufus and Martha. Factor in a serious relationship, which has long ended, with another member of the folk pantheon — with Suzzy Roche of the Roches, that produced yet another musical offspring, Lucy Wainwright Roche — and cue decades of songs, many of them about a complicated life in a family of musical royalty. Some of those songs have titles that don’t scan well in a family newspaper, including Loudon’s ditty about a fight for position at the breast of Rufus’s mother and Martha’s profane rocket aimed at her father’s shortcomings. Back and forth it goes, with Rufus’s “Dinner at Eight” revealing that supper at the Wainwrights was sometimes more dark indie movie than sitcom.


But as a clan they never let a song get in the way of firmer, more durable ties. On Friday many members of the family will gather at Town Hall to mark the recent release of Loudon Wainwright’s album “Older Than My Old Man Now” (2nd Story Sound Records), a bracing look back that includes references to — and performances by — various Wainwrights, Roches and McGarrigles. Even the departed are represented, with a spoken recitation of a meditation on family written by Loudon’s father, a columnist for Life magazine, along with the only song Loudon Wainwright ever wrote with McGarrigle, who died in 2010.


“Older” is a hilarious and self-lacerating take on both the bonds and bondage of family, full of duets and subtexts that would take a family therapist years to untangle. What emerges is common familial strife rendered in uncommon ways. As Loudon sings on the affecting “In C,” “And if families didn’t break apart, I suppose there’d be no need for art.”


Part of the family — Loudon, 65; Rufus, 38; Martha, 36; Ms. Roche, 55; and Lucy Wainwright Roche, 30 — recently assembled at Dixon Place on the Lower East Side, with exes, wives, grandchildren and friends milling about, to talk to David Carr about what it’s like to hear your life in song and then chime in on the chorus. These are edited excerpts from the conversation.


Q. Most extended families couldn’t even paint a room as a group, but you guys have played together for years. How do you decide on a set list?


RUFUS WAINWRIGHT That depends on whose show it is.


LOUDON WAINWRIGHT I’m the boss for Town Hall. Since everybody’s on the record, we’re going to do what we do on the record, but everyone is also going to get a chance to step out a little bit and do one of their own songs or whatever they want.


RUFUS This isn’t a new venture in terms of our careers. I remember when we were kids, Suzzy used to do Christmas shows, and I used to sing with my dad and mom when I was prepubescent, so it’s been this kind of ongoing theme that has been very successful.


SUZZY ROCHE There is something just physically enjoyable about singing together when you have that family thing. It is kind of a physical thing.


Q. Does it feel odd to sing a song by your dad that is about you?


RUFUS It’s very intense and weird. But that’s why I love it. For me personally I’m a big opera fan, I’m a big theater fan. I always gravitated toward that which is explosive and full of danger. And nothing is bigger than that, nothing gets more imbued with that, than family.


Q. Do you ever hear a song by a family member and think: That never happened?


MARTHA WAINWRIGHT I don’t think that a three-minute song can tell the whole story about anything. I think you can have a line and an element and a moment, and that can start the concept of a song but won’t tell the whole story.


Q. Rufus, on your new record, “Out of the Game” [Decca], you’re already talking to your baby daughter on “Montauk,” so the tradition continues.