WESTPORT — At 20 years old, Caissie St. Onge found herself working as David Letterman’s assistant, a far cry from the Massachusetts farm town where she grew up and attended college.

St. Onge arrived in New York in 1993 to intern for Letterman on the “Late Show with David Letterman” because she had to complete an entertainment internship for her film degree from Fitchburg State University. The only job requirement was the ability to drive stick-shift, which St. Onge could not do, but Letterman gave her the job anyway. Soon after, St. Onge moved into a tiny Greenwich Village apartment with her college boyfriend and now husband, Matt Debenham, a fiction writer.

When St. Onge later asked Letterman why he gave her the internship when she couldn’t fulfill the only required task, she remembers he said, “You went to a school that nobody cares about like I did, you have a weird name, and I felt like you’re going to need a little help. I figured you’re smart and you’ll figure it out. If you can’t drive the car, you’ll figure it out.”

St. Onge did figure it out, and said Letterman appreciated her working-class background and, ironically, that she wasn’t a superfan of his show.

“I wasn’t going crazy over him, and I think he wanted a certain amount of space to be regular. During that time, I feel like I was the person where he would tell regular stuff to — about weird foods he liked or whatever, because I would get a kick out if it,” St. Onge, now 45, said.

While many of St. Onge’s college peers watched Letterman each night, she worked the graveyard shift at a nursing home to put herself through college in three years. Once the

internship ended, St. Onge was hired as Letterman’s full-time production assistant, a job which required her to write letters for Letterman, thanking people and asking them to come on the show.

One day, St. Onge asked Letterman, “If these (letters) are coming from you, shouldn’t they be funny?” He said yes, but the letters had to be really funny for him to sign them. St. Onge began writing jokes in the letters and, through the editing process with Letterman, learned to hone a joke.

“It was a lot of real comedy 101 lessons. It was like grad school. Every night I would take this stack of letters into him and he’d have this red pen and just diagram out and say, ‘I see what you’re doing, here’s how to make it right,’ ” St. Onge said.

A few years later, one of Letterman’s producers left to work for “The Rosie O’Donnell Show” and asked St. Onge to join as O’Donnell’s assistant. She took the position, thinking she would have more opportunity to become a writer on a new show.

After six weeks as O’Donnell’s assistant, St. Onge was promoted to associate producer and, within the next few months, scored a writing job on the show, where she wrote song parodies and comedy bits. Around the time O’Donnnell’s show ended in 2002, St. Onge and her husband moved to Westport with their two young sons because she knew a fellow writer from the O’Donnell show who lived in Weston and liked the area.

As a working mom and artists with relatively less wealth than most Westport residents, St. Onge said she and her family stuck out in town amid the many finance dads and stay-at-home moms. “We live in the armpit of the train tracks and the highway,” St. Onge said of her home near the Saugatuck train station. Nonetheless, St. Onge said she was incredibly grateful for the hard-working stay-at-home moms who helped take care of her children when she and her husband were working or the trian ran late.

St. Onge now works as the co-executive producer of the Bravo talk show “Watch what Happens Live with Andy Cohen,” a position he has held for nine years. Between seasons and different television gigs, she has ghostwritten celebrity memoirs (names not disclosed), doctored the script for a Broadway musical and penned a young adult novel “Jane Jones: Worst. Vampire. Ever,” published by Penguin Random House.

A frequent tweeter, St. Onge said technology has enhanced the comedy business. “I think social media and technology have really democratized humor,” St. Onge said. Technology enables more people to share comedy, which has decreased the superfandom of a few specific comedians, thus making it easier to move on from idolizing some male comedians who, in the wake of the #MeToo movement, have been exposed of sexual harassment, St. Onge said.

Comedy is far from dying following the #MeToo movement, St. Onge said.

“People are still funny. Whenever people say everybody’s too politically correct and you can’t say anything anymore, I automatically know that person’s a lazy writer or a lazy humorist. Because if you can’t find something to be funny about without directly harming someone, then you’re not very good at your job,” St. Onge said. “People are rising to the occasion. And for people that are really talented, it’s not causing them to break a sweat at all.”

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