Cooper Koch Star-Studded Childhood: How His Mom’s Job Connected Him to Hollywood A-Listers! Cooper Koch, the 29-year-old breakout star of Netflix’s Monsters: The Lyle and Erik Menendez Story, has revealed a surprising Hollywood connection that predates his acting career.
During an August 4, 2025, appearance on Late Night with Seth Meyers, Koch shared how his mother, celebrity fitness trainer Kathy Kaehler, introduced him to stars like Kim Kardashian, Jennifer Aniston, and Julia Roberts when he was just a preteen. His candid anecdotes offer a glimpse into a childhood surrounded by fame and the unexpected ways those early encounters shaped his journey.
A Childhood Among Celebrities
Koch’s rise to fame came with his Emmy-nominated portrayal of Erik Menendez, but his brush with Hollywood began much earlier. Speaking to Seth Meyers, he explained that his mother’s role as a fitness trainer for A-list celebrities gave him unique access to stars as a child.
“My mom used to be a celebrity fitness trainer, and she trained them when I was a kid. When I was, like, 11, 12 years old,” Koch said. Growing up in Los Angeles, he would often stumble upon famous faces in the family’s garage gym, where Kaehler worked with clients like Kim and Khloé Kardashian.
“I’d sometimes wake up and be going to school,” Koch recalled. “Then I’d just walk into the garage and then, like, Khloé or Kim or whoever would be in there and be like, ‘Ah. Ok, cool.’” The casual encounters were a normal part of his childhood, but Koch kept them under wraps at school, joking, “I’m not a kiss and tell.”
Reconnecting with Icons
Koch’s early exposure to fame came full circle when he reintroduced himself to some of his mother’s former clients. He recounted a memorable moment with Jennifer Aniston at a party, where he mentioned his mother. “She was like, ‘That’s your mom!?’ Like, ‘Oh my god! And how’s your dad?’” Koch shared, highlighting Aniston’s warm recognition. Kaehler’s client list also included Julia Roberts, Michelle Pfeiffer, and “all the Friends girls,” making Koch’s childhood a star-studded affair.
These encounters, while exciting, were just the beginning. Koch’s role in Monsters led to a high-profile reconnection with Kim Kardashian, who facilitated a meeting with Erik and Lyle Menendez after watching an early screening of the series. “She loved it and started to get very fascinated with the story,” Koch said. A call from his stylist led to a FaceTime with Kardashian, who offered to arrange the visit. “All of a sudden, I’m on FaceTime with her. And she’s like, ‘Do you want to go down there and meet them?’ And then it happened that weekend,” he added.
A Bond Beyond the Screen
Koch’s meeting with the Menendez brothers forged a lasting connection. Following his Emmy nomination for Outstanding Actor in a Limited Series or Movie, Lyle Menendez called to congratulate him. “He was very, very sweet,” Koch told Entertainment Weekly’s The Awardist podcast in July, adding that Lyle jokingly envied his recent Wimbledon trip. “They’re doing really well,” he noted, reflecting on the brothers’ support for his portrayal of their story.
The actor’s ability to connect with both Hollywood stars and real-life figures like the Menendez brothers underscores his unique journey from a celebrity-adjacent childhood to a rising star in his own right.
A Bright Future Ahead
Koch’s appearance on Late Night highlights his growing prominence in Hollywood, bolstered by his mother’s legacy and his own talent. As he navigates fame, his stories of meeting icons like Aniston and Kardashian as a preteen add a relatable charm to his persona. With an Emmy nod and a hit Netflix series under his belt, Koch’s star is only rising, and fans are eager to see what’s next.
