Angelina Jolie and Brad Pitt's son, Knox, is no stranger to the red carpet.
In July 2008, the actors welcomed Knox and his twin sister, Vivienne, in Nice, France, joining their siblings Maddox, Pax, Zahara and Shiloh.
"They're pretty great people," Jolie told PEOPLE in October 2021. "Because there's so many of them, I think they've had a very significant effect on each other. It's not like I'm the head of anything. I'm very honest with my kids. And I'm very human with my kids."
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The Maria actress shared that she is "curious about all the different aspects of who they are" as she raises her children, emphasizing that her primary goal is to "be there to support and develop" their unique traits.
In addition to his film cameo as Kuku in Kung Fu Panda 3 alongside his mom and siblings, Knox, now 16, is carving out his own interests — one of which is learning sign language.
From his birth to his red carpet appearances, here's everything to know about Angelina Jolie and Brad Pitt's youngest son, Knox.
He and his twin sister were born in France
Jolie and Pitt welcomed fraternal twins, Knox Léon and Vivienne Marcheline, on July 12, 2008, in Nice, France. Knox was born a minute before his sister, weighing 5.3 lbs.
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Jolie hadn't formally announced her pregnancy, but debuted a baby bump at the Independent Spirit Awards in February of that year. A few months later, Jolie's costar, Jack Black, accidentally revealed that the actress was expecting twins.
Following their birth, the family of eight spent the summer at the Château Miraval in Provence, France. With two new additions, Pitt described the household to PEOPLE as a "cuckoo's nest."
Jolie called it "chaos" but added that they were "managing it and having a wonderful time," with plenty of help from the twins’ older siblings, who helped to pick out the babies' clothes and "change and hold them."
“It’s sweet – they are little mommies," Jolie said.
He was named after Pitt’s grandfather
PEOPLE previously reported that Knox was named after Pitt's grandfather, Hal Knox Hillhouse. Additionally, Pitt explained to PEOPLE and Hello! Magazine that Léon "is a classic French name."
Knox's twin sister's name, however, carries a tribute to Jolie's side of the family. Her middle name was chosen to honor Jolie's mother, Marcheline Bertrand, who died from cancer just over a year before Vivienne's birth.
He shared his dad's passion for music as a baby
Shortly after his birth, Pitt shared with PEOPLE which parent each of the twins took after.
"I dare to say that Viv is proving to resemble Angie in spirit, attitude and physicality. She is quite elegant like her mother," he said. "And Knox, he’s a bit of me. He likes music like his dad."
He has done voice acting
Knox had a role in 2016's Kung Fu Panda 3 as the voice of Kuku, the triplet of Meng Meng and Shuai Shuai. Although Knox was joined by his siblings, Jolie told Entertainment Tonight in January 2016 that they were "kind of shy."
"They don't really want to be actors, but I didn't want them to miss the opportunity. They came in, and they had a lot of fun with it," she said.
When given the offer years later to make cameos in Maleficent: Mistress of Evil with their mom, Knox and his siblings weren't interested.
“None of my kids want to be actors,” Jolie told PEOPLE in October 2019. “[They’re into] business, humanitarian affairs, things like that.”
He’s joined his mom on red carpets
As a kid, Knox and his siblings frequently appeared on the red carpet with their mom, joining her for the premiere of First They Killed My Father and Maleficent: Mistress of Evil. But after attending the London premiere of Jolie's Marvel film Eternals in October 2021, Knox seemed to opt for a life away from the spotlight.
Three years later, Jolie told E! News that her kids are "especially shy" and "want to be private."
However, supporting his mom as she received critical acclaim for her new filmMariain November 2024, Knox made a rare appearance in the spotlight when the mother-son duo walked the red carpet at the Governor's Awards in Los Angeles.
He was learning sign language when he was a child
During an appearance on BBC Radio 4's Women's Hour in 2016, Jolie opened up about enjoying the way her kids have developed unique personalities and interests — including all learning different languages.
“I asked them what languages they wanted to learn," she said, revealing that Knox had chosen to study sign language.
As for his siblings, Jolie shared that "Shi is learning Khmai, which is a Cambodian language, Pax is focusing on Vietnamese, Mad has taken to German and Russian, Z is speaking French [and] Vivienne really wanted to learn Arabic."