Legendary South African actor John Kani, 81, has the fondest memories of working with Chadwick Boseman in Black Panther.
Kani, who played T'Chaka, the father of Boseman's T'Challa's, in the 2018 film, opened up about his experience while at the L.A. premiere of Mufasa: The Lion King on Dec. 9.
"Here is this kid. He is incredible. I'm with my son, Atandwa. And both of them were like my children, they called me 'daddy' right through," he told PEOPLE. In fact, Kani says he and Boseman forged such a tight bond while they were working that when Boseman died in 2020, Kani received an influx of sympathy from people who thought he lost his biological son.
Related: Lupita Nyong'o Honors Chadwick Boseman on What Would Have Been His 48th Birthday in Moving Post
"When Chadwick passed away, I got a thousand messages of deepest condolences," he said. "At first I tried to explain, 'No, he's not my son, he's my son in the movie...' [but] I [have] just accepted now that he was my son. An incredible, true consummate professional," Kani said.
As for Boseman's work ethic, Kani revealed the late actor was tireless when it came to getting the scenes in the Marvel film right.
"He wanted to be sure. In Chad we had a sense of time," Kani shared. "He worked on a schedule he only knew, [and understood] that we haven't gotten enough time. He wanted a 25-hour day so he could get the opportunity to say everything he wanted to say. That was my experience with Chadwick."
To commemorate what would have been Boseman's 48th birthday on Nov. 29, his former costar and close friend, Lupita Nyong'o, took to Instagram to share a sweet photo of herself and the late actor.
In the caption, Nyong'o shared a quote from the 20th century Dutch Catholic priest and theologian Henri Nouwen that read, "Those you have loved deeply and who have died live on in you, not just as memories but as real presences."
"Remembering that Chadwick Boseman was born on this day. 🙏🏿👑💜," she added.
As for Kani, come Dec. 20, he will be reprising his role as Rafiki in Barry Jenkins' prequel Mufasa: The Lion King.
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"I was Rafiki in 2019 with Jon Favreau and coming back to work with Barry Jenkins now, it felt like [putting on] my old jacket. You know that jacket in the wardrobe that everybody says is out of fashion, it's not looking nice. But when you put it on, it's still got that little aroma, and it gives you back those memories," he said of working on the project.
Kani also found some similarities between himself and his character, telling PEOPLE he was essentially the grandfather of the cast.
"Going back to Rafiki was an incredible journey," he said. "We're both over 80, that's the other thing. I too, now have seven children and 10 grandchildren. So talking to Blue Ivy as Kiara, I knew [how to do] that [because] I'm always talking to grandchildren."