All About Colin Jost’s Younger Brother Casey Jost (and the Behind-the-Scenes Role He Plays on an Iconic Comedy Show)

'Saturday Night Live' star Colin Jost and his brother Casey Jost are writing a movie together

Colin Jost isn’t the only funny one in the family — his younger brother, Casey Jost, also works in comedy.

Born in 1985, Casey grew up with his older brother on Staten Island. Just like Colin, he has gone on to build a career in entertainment, working across podcasts, television writing and film production.

The siblings have long been close, often sharing photos and videos from their childhood. Now, the comedian shares a daughter with his wife, Lisa Kleinman, who also works in the entertainment industry. Casey continues to work as a writer and producer and in August 2021, it was announced that he and Colin would be writing the next Teenage Mutant Ninja Turtles film.

In 2023, Casey went on the Funbearable podcast and talked about working with his brother. "My biggest takeaway from this process is just how insanely talented my brother is," he said. "He's been on SNL for so long and he's written 10,000 scripts. He's just been a savant his whole life."

From his Staten Island upbringing to his current work and family, here’s everything to know about Colin Jost’s brother Casey Jost.

He’s a lifelong New Yorker

Casey has spent his entire life as a New Yorker. Born in 1985, he grew up in Grymes Hill, Staten Island.

His and Colin's father, Daniel A. Jost, taught at Staten Island Technical High School and their mother, Kerry J. Kelly, served as chief medical officer for the New York City Fire Department.

Like Colin, Casey attended Regis High School, an all-boys private school in Manhattan. Now, the comedian lives with his wife, daughter and dog.

He’s a writer, producer and podcast host

In his long-running career across comedy and entertainment, Casey wears many hats. In the television space, he is the executive producer of Impractical Jokers, a comedic reality show that uses hidden cameras. The show began in 2011 and has had more than 10 seasons.

Additionally, Casey co-hosts the Give it a Chance podcast with Kevin Devine on iHeart Radio. In each episode, the pair discuss a famous (or “famously despised”) pop song in search of “anything that makes it good, as well as what makes it bad.”

He and Colin are writing the next Teenage Mutant Ninja Turtles movie

On Aug. 2, 2021, Deadline announced that the Jost brothers were tapped to write an untitled Teenage Mutant Ninja Turtles film, produced by Paramount Pictures.

In 2023, he went on the Funbearable podcast and talked more about the project, noting that they had sent in a draft of their script.

"Colin was tapped to do it, and he said, 'You know, my brother and I grew up with the turtles, and I would love to do it with him,' and they said, 'Oh, absolutely, we love the idea that these brothers are writing for these brothers.' So we wanted to lean into their brotherhood," Casey said.

The comedian continued, "We tried to pull elements from our favorite movies too so there might be some moments that remind you of Ghostbusters or other fun action comedies."

He's been married for more than a decade

Casey married his wife, Lisa Kleinman, on June 21, 2014.

The couple are both veterans of the theater group Upright Citizens Brigade and like her husband, Lisa works in entertainment. According to her website, she’s a development executive, producer, writer and director with a background in everything from social media to scripted and unscripted work and animation.

To date, Lisa has produced, created and developed projects for Mashable, Facebook, Comedy Central and Condé Nast, among many others.

He’s a father and uncle

In December 2021, Casey became a first-time father to daughter Mari Klein.

The comedian is also an uncle. In 2021, Colin became a father to a son named Cosmo whom he shares with his wife Scarlett Johansson. Colin is also a stepfather to daughter Rose Dorothy whom Johansson shares with Romain Dauriac.