If there’s one thing that humorist Patricia Marx knows, it’s that mothers know best. So, when she had her first piece published in the Atlantic back in the late ’70s, her mom goaded her into calling the person who had done the illustrations. That artist was Roz Chast.

That single phone call has led to a more than 40-year friendship between the pair.

“This was back when magazines were still being printed on stone,” Chast, a Ridgefield resident, joked. “We were practically children and at the very beginning of our work lives.”

That original article, Marx noted is weirdly current now as it was called, “What Should We Do About the Russian?”

“I’m not even sure how I got her phone number, but that was in the days when people weren’t paranoid, so I may have just called the editor and he gave it to me,” Marx said.

Chast remembers a “nice chat” and it was the first time that anyone she had illustrated for ever called her up to compliment her.

“Basically, Patty’s mom set us up on a playdate,” she said. “We knew some people in common and met a couple of years later at a dinner. Patty was writing a children’s book and asked if I wanted to illustrate it, and I did, and it was a wonderful collaboration. We’re on the longest playdate in the world.”

Both have had successful careers — Chast is a cartoonist for The New Yorker, while Marx is a humorist for the publication and was one of the first-ever female members of the Harvard Lampoon and a writer for “Saturday Night Live.”

Over the years, the two have married their talents together for a series of four best-selling children’s books and a collection of edicts from Marx’s mother called “Why Don’t You Write My Eulogy Now So I Can Correct It? A Mother’s Suggestions.” Chast also authored The New York Times best-selling memoir, “Can’t We Talk About Something More Pleasant?”

“We are both very prompt, and I am very appreciative that we are both always on time,” Marx said. “We also work together well because we’re both a little better at one thing, but the secondary thing we both have a good sense of. We might suggest something and it usually stays in.”

Chast adds the overlap between the writing and the drawing makes the collaboration work really well. A shared sense of humor helps as well.

On Jan. 14, the duo’s latest book comes out, “You Can Only Yell at Me for One Thing at a Time: Rules for Couples,” a collection of comical new relationship tips.

“This comes from anyone who has ever been in a relationship with a significant other,” Chast noted. “It’s about the complexity of the relationship and the mixed feelings you may have, and how so many of the disagreements you may have are trivial and huge at the same time.”

Marx and Chast will do a talk at the Darien Community Association with Barrett Bookstore on Jan. 15, reading excerpts from their new work.

Some of the tips in the book include such gems as “If you must breathe, don’t breathe so loudly,” “It is easier to stay inside and wait for the snow to melt than to fight about who should shovel,” and “Queen-sized beds, king-sized blankets.”

Other topics include fights over the thermostat and domestic management, regardless of who the couple is — straight, gay or even a pair of animals!

“These are topics that Roz and I have talked a lot about, so it seemed a natural way to go,” Marx said. “I don’t think this book could have been written by someone 22 years old who hasn’t lived with someone for a long time. They would have a very different idea on what it’s like to live with that person you are in love with.”

There were plenty of ideas left on the table, as the book could only cover so many issues, and the two chose the ones they felt were funniest and would look good visually.

Another fun part of their friendship is they are both ukulele players and at the Darien event, they will be bringing their instruments along and playing in between some of their readings.

“We have a band called Ukulear Meltdown and we like to mix the reading up with slides and ukulele accomplishment,” Marx said. “It’s always fun.”

The two picked up the instrument about two years ago when Marx was invited to a wedding that was taking place during an eclipse and guests were asked to bring an instrument to play “Here Comes the Sun” after the sun went down.

“I didn’t play anything and I thought, ‘how hard could a ukulele be?’ so I bought one and I first fell in love with the color, and then fell in love with the playing,” Marx said. “I showed it to Roz and told her she had to get one. It was $49, turquoise and just fantastic.”

The band’s specialty is playing songs in the public domain because Marx rewrites them.

“We have an imagined history that we were very big in the ’60s and ’70s, we played at Woodstock but they forgot to put film in the camera, so we didn’t appear in the movie, and we played with Bob Dylan and were the ones who told him to go nasal,” Marx laughed, before Chast added that their imaginative history also included an appearance on “The Ed Sullivan Show.”

In 2020, Marx and Chast will be starting work on a new book, though the topic is still yet to be revealed. For now, they are looking forward to starting the year off with a series of readings.

“We have a good time on stage, and the audience seems to enjoy it,” Chast said. “It’s a little bit more of a show than just reading. We cater to more of an ADD crowd with a lot going on.”

The talk will begin at 7:30 p.m. Tickets are required for entry and are available at dariendca.org.