Larry David Gave Rob McElhenney Some Valuable Advice For It's Always Sunny

"It's Always Sunny in Philadelphia" is a sitcom unlike any other, but it still has its fair share of influences. A huge inspiration for the series' creators was Larry David, the co-creator of the global hit "Seinfeld" and creator and star of the hilarious HBO series "Curb Your Enthusiasm," which may or may not be entering its final season. But it wasn't just David's work that inspired "Sunny" showrunner Rob McElhenney, it was David's words — and his laughter — that also served as motivation. In fact, the 76-year-old comedian is connected to "Sunny" in more ways than you might think.

Before Kaitlin Olson was Sweet Dee, she also had a recurring role in "Curb" as Becky, the sister of David's long-time on-screen girlfriend Cheryl. Olson first appeared in the show's very first season and later reprised her role in season 10. Olson described her experience on David's production as "amazing," in a 2013 Vanity Fair interview. "He's a genius," she continued. "And yelling in his face cracks him up. My kind of guy."

Unlike most sitcoms, "Curb" gives its actors lots of room for improvisation — a feature of the show that Olson loved, given her background in improv at the Groundlings Theater. 

"It was the first time that I'd been given the freedom to say whatever I wanted," she recalled in a 2008 interview. "Normally, I don't know if people know this, but when you go and get a job on a scripted show, you are not allowed to change the words at all. [...] The actors have their jobs and the writers have their jobs and they're completely separate. So getting to be involved in the creative writing process of it was really awesome. I loved it."

Olson's role in "Curb" laid the groundwork for her part in "Sunny" — in more ways than one.

The creative freedom Kaitlin Olson was given on "Curb" was later mirrored in her experience on the "Sunny" set. "It's the best of both worlds," she went on. "It's hilariously scripted, but we also play around when we're shooting because the writers are the actors. So we can say whatever we want and if it doesn't work, we go back to how it was scripted or you come up with something else."

The "Champions" actor knew working under a comedic legend like Larry David was a major accomplishment. "I'm not the ballsiest person, so I was very proud of myself for getting it," Olson told Buzzfeed News in 2015. The role in "Curb" also helped her land a part in "It's Always Sunny." "I knew her work from seeing her in 'Curb,'" co-creator and star Glenn Howerton added. "We wanted to find somebody who could be as funny as the guys, and we felt a lot of times in comedies, girls are so often relegated to the, 'Oh, you guys' role."

Olson's involvement in "Sunny" is probably the reason David ended up seeing the show — and falling in love with it. "We had Larry come to a premiere," Rob McElhenney said to Indiewire in 2016, "and I didn't care what was happening. I was just listening for that very distinctive laugh behind me. We got like, two. Later on, I said something, and they go, 'Larry laughed twice. That's two more than he'll laugh at anything else.'"

But it wasn't just a couple laughs that McElhenney got from David. He also got a piece of invaluable advice about how to run his series — and how to end it.

"Sunny" became the longest-running live-action sitcom in the history of American television when season 15 debuted back in 2021, has already been renewed through season 18. The series remains hugely popular, but why have the show's creators continued working on the same project for so many years, presumably missing out on opportunities to expand their careers?

"At a certain point, we might look at this and go, 'Yeah, we did it and it's time to move on,' and all that kind of stuff," Glenn Howerton admitted to GQ in 2019. "But I think at the same time the way I see it, we're more like a band than a show now, where we all go off into our side projects, but like, this is the band, and if we feel like putting out another album, we'll put out another album. At this point, it doesn't really make sense to end the show in any official capacity."

The idea for the "when-we-feel-like-it" model came from Larry David, who has sometimes waited several years to release new seasons of "Curb."

"It's possible that moving forward we move to sort of like a 'Curb Your Enthusiasm' model if we can get away with it," Howerton continued. "Larry David actually pulled Rob aside at some kind of a function and told him, 'One piece of advice I'll give you guys: Don't ever end the show. Just don't end it!' I think he figured that out after 'Seinfeld.' I think he was really burned out. But with 'Curb' he knows he might want to come back to it years down the line."

The gritty FX series has followed a slightly more consistent output schedule than HBO's "Curb," rarely taking breaks of more than a year between seasons, but this gap might widen as the years go on. Still, that's better than the show ending forever, right?

Despite putting out new seasons of "Sunny" year after year, the main cast has managed to do their fair share of solo and collaborative projects over the course of the comedy's nearly two-decades-long run. Glenn Howerton starred in the 2023 biographical film "BlackBerry" and even led his own series, "A.P. Bio," for four seasons. Kaitlin Olson has had several recurring roles in TV comedies like "Hacks" and "New Girl" and starred in "The Mick" for its two-season run. She has also done voice acting in popular animated works like "Finding Dory," "Family Guy" and "Bob's Burgers."

Charlie Day has starred in blockbusters like "Horrible Bosses" and "Pacific Rim" and recently made his directorial debut with "Fool's Paradise." He also co-created the popular Apple TV series "Mythic Quest" with Rob McElhenney in 2020. McElhenney stars in the show and has done his own share of side quests (pun intended), including co-owning the Wrexham football team with Ryan Reynolds and starring in a docuseries about it. Even Danny DeVito at 78 years old still finds the time to star in whimsical family films like "Jumanji: The Next Level" and "Haunted Mansion."

With all the other work the "Sunny" cast has managed to put out over the years, there's no sign of them burning out any time soon. The seasons may take longer to come out, but as long as they keep that tap a-flowing, the fans will stay happy and the series will live on. Here's to 16 more seasons!