Roz Chast, a cartoonist for The New Yorker, and Patricia Marx, a humorist and staff writer at that magazine, have been friends ever since Marx’s mother forced them together in the late 1970s. When Marx, one of the first female members of The Harvard Lampoon, had her first humor piece published (in The Atlantic) Chast illustrated the story. Marx’s mother, now 92 and according to her daughter still a woman of strong opinions, thought Marx should call the person who had illustrated her work.

“It was stupid, but I always do what my mother tells me,” Marx said.

“It was like a play date,” said Chast.

Chast’s mother, who died in 2009, was perhaps even more formidable than Marx’s mother, as readers learned from “Can’t We Talk About Something More Pleasant,” Chast’s harrowing memoir of her parents’ final years. And she certainly did not believe in play dates, as we will discover. Marx grew up in a suburb of Philadelphia, one of three children; Chast, an only child, grew up in Brooklyn.

Over the years, the two have collaborated on four children’s books, and this past year, on a collection of edicts from Marx’s mother titled, “Why Don’t You Write My Eulogy So I Can Correct It? A Mother’s Suggestions,” out April 1.

They have also formed a two-woman ukulele band.

The other day, Chast and Marx were nesting on the sofa in Marx’s East Side apartment. They played through their (short) repertoire of uke songs — rewritten classics, like “Park, park, park your car, somewhere near the curb ... sung to the tune of “Row, Row, Row Your Boat — and talked about their singular mothers.

Chast (Looking up at Marx): I am so short-waisted, when I sit down, I am shorter than you.

Marx: But I am sitting better than you. Sitting is my strength.

Chast: I like to sit. I sit all day. And into the night. This is like the world’s two laziest people.

Though your childhoods were very different, your moms were similar in many ways. Can you introduce them?

Chast: My mother was an assistant principal in an elementary school in Brooklyn. You would not want to make an enemy of her. She very much believed in herself and in her judgment. She was very smart. She had wanted to be a classical pianist, but she grew up very poor and she graduated from college during the Depression and her career took a different turn.

Marx: My mother is not musical at all. She probably doesn’t know when to clap at the end of a performance. She was anti-music. My father was very musical and played the piano all night long, which she said was anti-social, which it was. My mom, like Roz’s mother, is decisive and an absolutist. She has a very good eye.

Chast: My mother had no eye. Not even one.

Speaking of music, how did the band come about?

Marx: I went to a wedding and the guests were asked to bring an instrument and I can’t play a musical instrument, but I thought, “How hard can it be to play a ukulele?” So I bought one on Amazon and played “Here Comes the Sun” to serenade the couple, and I showed it to Roz.

Chast: I fell in love with it because it’s the parakeet of instruments: It’s so cute and so turquoise and so cheap. (Chast has lived with generations of parakeets, and two parrots.)

Marx: And we started goofing around on email, coming up with our musical history just to make each other laugh. We were a sensation. We call our band the Ukulear Meltdown. We started as the Daily Ukuleles. Then we became the Weekly Ukuleles, then the Monthly Ukuleles, and then the Never Ukuleles. That was when Meg Wolitzer and Lorrie Moore were in the group, but we fired them because they had talent and knew how to play, which we consider pandering to the audience.

(Editor’s note: This is a fabrication. Wolitzer and Moore were never in the band.)

Chast: Maybe we forgot our history, with all the drugs we were doing.

(General discussion of the drugs of yore, though Marx swore up and down that back in the day, drugs “never had any effect on me.”)

Marx: My mother does not like to admit that anything is ever sad or wrong, so if my father would say something like, “During the Depression ...” She’d say, “Oh, Dick, there was no Depression.” She was like a Depression denier.

Chast: My mother was more like a personal depression denier. Her whole thing was if you were sad, she would say, “Stop staring at your navel.” When I grew up, I didn’t know what other people talked to each other about, because there were so many things we didn’t talk about.

Marx: My mother was very can-do. She told me, “Nobody needs more than four hours of sleep.” I hate sleeping. Guilt gets me up.

Chast: I like to sleep because I’m interested in dreaming, but it’s more like profound laziness or momentum. Once I’m awake, going to sleep just seems so annoying, and once I’m sleeping, waking up seems so annoying.

Both of you had parents who were deeply bonded to each other. Patty, your father thought your mother looked like Jacqueline Bisset. And your mother thought he should change his shirt. Roz, your parents were born the same year and proclaimed they were soul mates. Let’s hear more about their couplehoods.

Marx: My mom did everything herself because it was easier and she liked things done a certain way. Once she went away for a week and my father relied so much on her that she put name tags on my father’s clothes that said things like “Wear with khaki pants Thursday.”

Chast: My mother was the one who made all the decisions and ran the show. My father never learned how to drive because it made him profoundly anxious, so she did all the driving, even though she was an anxious driver, but it was a different sort of anxiety. My father didn’t want to do anything. I think he would have been happy staying in the apartment, puttering around and reading The Times.

Marx: My mother was very blunt. We grew up before they invented psychology. So my mother felt free to criticize without thinking there would be horrible consequences. She called it constructive criticism, and I valued it because I knew she was telling the truth. She once read a piece of mine in Time magazine and said, “Guess what? I hate it! But if enough people like it, I’ll change my mind,” which I completely understood.

Chast: My mother never offered that many opinions about my work, though sometimes she would get mad and say, “You’re using me and Daddy to make fun of.” I’d say, “This is a general statement about, um ...”

Marx: And she bought that?

Would you both say that your childhoods were the gift that keeps on giving, workwise?

Marx: Unlike Roz, I had a really good childhood. I learned the word bourgeois so I could say, “You are so bourgeois!” to my parents, because I was a communist. A communist in the suburbs. I envy you your worst childhood.

Chast: My parents didn’t try and make it bad. They were working all the time. My mother had this idea that if I ever socialized with other kids, at the very best I would come home with impetigo and at the worst I would be learning things I shouldn’t be learning. So my childhood was about avoiding other children. It was like being locked in a Skinner box.

I hated being a kid. Once I got out of college and started my life in New York, it was a profound reset. At art school it was still about making friends and learning how to present yourself. Learning who you are. In some ways that’s still a huge mystery to me. But I do like to work. It was such a relief to not have to think about any of that stuff anymore. It was very clean: You like the work, you give me money.

Marx: I am ashamed to admit I liked childhood. I enjoyed that somebody was handling the logistics. I knew you weren’t supposed to like childhood, so one day I told my mother I was running away. She said, “That’s OK, I’ll pack you a lunch and you can go wherever you want as long as you don’t cross the street.”

Patty’s mother had such specific ideas about fashion: no sleeves with names, no plaids on white backgrounds. Roz, did your mother have opinions about what people wore?

Chast: My mother thought being concerned about appearance was demeaning and if you were a woman and cared about things, you got what you deserved.

Marx: Growing up with someone who believed there was a right or a wrong is ultimately dangerous because you believed you could make a wrong decision, and the truth is, you can’t make that much of a wrong decision about a plaid.

Chast: When I was younger, I had this dress Bill [Chast’s husband, Bill Franzen] liked. It was blue and white stripes, and I would wear it with a little red belt. My mother saw me in it one day and said, “Va-va-voom!” And I never wore it again. Because the idea that anybody could look at me and go, “Va-va-voom!” was, you know, a nightmare.

What is your most important legacy from your mothers?

Chast: Both of my parents thought that whatever you did for a living, you should love it. My mother loved being an assistant principal. Even though I identified more with my father, the fact that she didn’t apologize to anybody for who she was or what she wanted to do, I think filtered down. I never felt like I had to apologize for being a female cartoonist. I never even thought about the fact that I was a female cartoonist.

Marx: When I was growing up, my parents wanted me to be a doctor, marry a doctor and have a doctor. That was just a given. Then, when I wasn’t a doctor or even a lawyer, my parents adjusted and being a writer was the best thing to do. The legacy my mother impressed upon me is that you have to work hard and you don’t give up and you don’t whine and that’s the deal.

Chast: Nobody’s going to hand you anything and hopefully you like what you’re doing. It’s like us with the band. We’ve made our millions and still we keep playing.

Marx: We just wish we were normal people, who could go to the grocery store without being mobbed.

This interview has been edited and condensed, overworked and upended. The editors trust the subjects will understand the process was in their best interests.

This article originally appeared in The New York Times.