“The world isn’t the same brother,” Diesel wrote of his former co-star on what would’ve been his 50th birthday

Julia Moore is a digital news writer at PEOPLE. A graduate of Northwestern University, she has been working at PEOPLE since 2022.

Paul Walker and Vin Diesel smile together in a throwback photo from 2010 shared by Diesel on Instagram. PHOTO: 

Vin Diesel is remembering his friend Paul Walker.

Diesel, 56, shared a touching tribute to Walker, who died in 2013, to honor the late actor’s 50th birthday on Tuesday.

“A decade… ten long years… and yet it feels like yesterday when we were singing happy birthday to you for the big 40!” the Fast X star wrote, reflecting on the upcoming tenth anniversary of Walker’s death and the last birthday they celebrated together.

“The world isn’t the same brother… as a species, one might say we are struggling. But I think of you, and I smile and know everything is going to be alright,” Diesel wrote.

Diesel then shared the backstory of the photo — which featured a younger looking version of the two actors; Walker’s arm around Diesel, and Diesel holding what looks like a cocktail shaker.

“For me this picture represents the moment I knew we would be brothers for eternity,” Diesel explained. “January 2010, the night before you and I went to Haiti… the passion and joy you had to simply help people. You said first responders shouldn’t have to wait for anyone… and that you wanted to dedicate your life to that. First responders… that was your true self, and you were sharing it with me, your brother.”

The earthquake that struck Haiti in 2010 — widely recognized as one of the worst natural disasters in modern history — prompted Walker to not only visit with Diesel and help the rescue and recovery efforts, but also to start Reach Out Worldwide, a charity dedicated to helping people devastated by natural disasters.

The actor was leaving an event hosted by the charity when he died in a car accident in November 2013.

Diesel also shared that his son, Vincent, 13, saw him looking at the photo of his younger self and Walker and said, “‘That’s such a timeless photo, Dad… one that will live on for generations of humanity.’”

Vincent added, “‘It’s why I want to build cars, for him,’” Diesel shared in the post.

Vin Diesel and Paul Walker on the “Fast & Furious” red carpet in 2009.

Meadow Walker, the daughter of the late actor, also shared a tribute on Tuesday in honor of her father’s birthday.

“Happy birthday to my guardian angel 🤍,” the model and actress wrote alongside a sweet black-and-white photo from her childhood. “Thank you for your love, guidance, friendship, sunshine and for raising me to see all of the beauty in the world. You are the most kind, humble, generous and caring soul I know. You taught me at a young age to always treat everyone with respect, to do good and to take care of our planet.”

She added, “I love you and miss you every day.”

Paul Walker and his daughter Meadow Walker. MEADOW WALKER/INSTAGRAM

The 24-year-old has spent much of this year paying tribute to her father, as she made a cameo in the newest Fast and Furious installment, Fast X, this spring.

“Thanks to my dad, I was born into the fast family. I can’t believe now I get to be up there too. With those who have been around to see me grow up,” she wrote in a post on Instagram announcing the cameo. “I am so blessed to be able to honor my father’s legacy and share this with him forever.”

Meadow’s cameo was a special one for the cast members, too.

“It did something to my soul, to see her want to honor her father and to contribute in her own way to his life’s work,” Diesel told PEOPLE of the appearance. “… It meant everything.”

Michelle Rodriguez said, “It’s everything to us because [Paul’s] memory is never going to die within the franchise, so as long as we’re doing it, we have to maintain that, [keeping his] energy alive.”

Meadow is now “woven into the fabric forever,” Jordana Brewster said, adding, “To have her be on set and work her butt off was really, really inspiring.”

The cast of ‘The Fast And The Furious’ in 2001.

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In Fast X, Meadow stars as a flight attendant who hands Jakob Toretto (John Cena) a few small bottles of alcohol.

Walker starred in the first seven movies of the action franchise. He made his final appearance as Brian O’Conner in Furious 7, which debuted in 2015. Filming was completed with help from his brothers, Caleb and Cody Walker, who starred as body doubles for his character in the wake of his death.