Clooney, 64, caught up exclusively with PEOPLE on the red carpet for the Los Angeles premiere of his latest film, Jay Kelly, on Thursday, Oct. 23. During the conversation, PEOPLE asked the actor if he had any stories involving his aunt, famous singer Rosemary Clooney, who died in 2002.
George shared that he worked as Rosemary's driver when he was first trying to break into Hollywood -- and he ended up driving a number of famous artists.
"I remember being on the road [...] I was my Aunt Rosemary's driver when she was singing," he recalled.
"And I hadn't known her much when I was young because I lived in Kentucky. She was the Hollywood aunt. So I came out to make a living and I was her driver. And I got to drive [her] and Tony Bennett, and all of these really wonderful singers around for a year," he added.
The Oceans 11 star said that being in such close proximity to major stars taught him an important lesson early in his career.
"I got a really good life lesson in success and failure, and handling it. And I always remember that [...] I felt very lucky that I got that lesson early in time," he said.
George went on to say that he even once got yelled at by Frank Sinatra, which he said he wears as a badge of pride.
"I remember he was mad at me once because I led this boycott about [...] some press freedoms, and he called me because people thought he was sick and there were helicopters flying over his [home], and he called me going, 'It's not working what you're doing!' "
The Oscar winner also opened up about his decades-long friendships in the industry, specifically noting that he believes it's important to stay close to the people who knew you before you were famous.
"Well, I mean, most of my friends [...] we've been friends for 40 years. I slept on their couch when I was broke. And so they're always around when things and people are giving you too much credit,"
he explained.
He added, "They're the first people to remind you that they're full of crap. That's always helpful. It's helpful to have people that know you long before you were defined by something else, by movies you've done or work you've done and that kind of thing."