Harry Belafonte's Daughter Says Sidney Poitier's Death Is 'Most Difficult Thing' He's Had to Fathom

Shari Belafonte is revealing how the Oscar winner’s passing is affecting her dad after their decades-long friendship

Harry Belafonte and Sidney Poitier were close friends for almost 80 years and fought for civil rights side by side.

Now, Harry, 94, is deep in mourning for Poiter, who died Thursday evening at the age of 94.

The singer's daughter Shari Belafonte told PEOPLE, "Losing Sidney is probably the most difficult thing my father has had to fathom, more so than losing Martin L. King."

"They were closer than brothers," says Shari, 67. "They have known and loved each other for more than 70 years, collaborating, living life to the fullest. While Harry was much more vocal and seemingly more instrumental in the civil rights movement via his stage presence and his navigating the dynamics between Leaders and politicians, Sidney broke those barriers in a much more creative way by taking a stand in the characters he portrayed so brilliantly on film."

She added, "They both focused on making this world a better place for all people, not just people of color. We grieve for his loss and for his wife and children, our extended family."

Sidney Poitier and Harry Belafonte. Alberto E. Rodriguez/Getty

In his own statement, Harry said, "For over 80 years, Sidney and I laughed, cried and made as much mischief as we could. He was truly my brother and partner in trying to make this world a little better. He certainly made mine a whole lot better.

The first Black man to win an Oscar and the first Black solo artist to sell a million LPs met in the mid-1940s while working at The American Negro Theatre in New York City when they were both 20.

At the time, Poitier was working as a janitor in exchange for acting classes and Harry was a stagehand. Both were of West Indian heritage and they bonded over their similar upbringings. Harry was cast in his first acting gig at the theatre, but when he was too sick to perform, his understudy, Poitier, stepped in.

Shari Belafonte. on Kopaloff/FilmMagic

The two lifelong friends also managed to make a huge mark on the civil rights movement. In 1964, Harry convinced Poitier to help him deliver $70,000 to Freedom Summer volunteers in Mississippi, according to a 2017 op-ed by The New York Times.

On the journey to make the delivery, the two were chased by armed Klansmen until they reached the predominantly Black neighborhood in Greenwood, Mississippi.

Martin Luther King Jr. once said of Poitier, "He is a man of great depth, a man of great social concern, a man who is dedicated to human rights and freedom. Here is a man who, in the words we so often hear now, is a soul brother," according to the Times.

Both Poitier and Harry helped organize the March on Washington and helped plan King's memorial after his assassination.

According to the Times, Harry has said of Poitier, "I don't think anyone [else] in the world could have been anointed with the responsibility of creating a whole new image of Black people, and especially Black men."

Archive Photos/Getty

In his 1972 directorial debut, Poitier cast Harry in Buck and the Preacher. The late icon later directed 1974's Uptown Saturday Night which also starred himself and Harry.

Poitier's career and legacy are indelibly tied to the civil rights movement and progress for the Black community around the world.

He won the Best Actor Academy Award — the first Black man to do so — for his role in Lilies of the Field, as Homer Smith, a handyman building a chapel in the desert.

In 1967, he released three iconic films: To Sir With Love, In the Heat of the Night and Guess Who's Coming to Dinner. They all explored race and class in provocative ways, with Sir casting Poitier as a teacher in a working-class, white London school. Dinner saw him waging a war of the heart opposite Katharine Hepburn and Spencer Tracy, as a Black man in love with a white woman (Katharine Houghton). It was remarkably timely, given the Supreme Court's ruling that same year on interracial marriage in Loving v. Virginia.

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But it was the groundbreaking In the Heat of the Night where Poitier played his most iconic character: Det. Virgil Tibbs.

The story follows Tibbs as he waits for a train in Mississippi when he is unceremoniously arrested for murder. Soon, the police chief (Rod Steiger, who won an Oscar for his performance) learns that Tibbs is actually a hotshot Philadelphia detective, and an expert in homicide, and asks him to consult. The film's racial tension mounts until the white suspect slaps Tibbs in the face. In a crucial moment, Tibbs returns the blow.

Poitier's character was initially meant to walk away from the slap, not return it.

Film Publicity Archive/United Archives via Getty

"You can't do it," Poitier declared to the film's producer. "You certainly can't do it with me." The actor insisted on slapping the suspect back. "I go in front of a camera with a responsibility to be at least respectful of certain values," Poitier told the Museum of Living History about the film. "My values are not disconnected from the values of the Black community."

The actor made a rare public appearance in April 2017 to commemorate the 50th anniversary of the film.

His costar Lee Grant told PEOPLE at the time that Poitier's powerful performance was not only critical to the film's creative and commercial success, but it also made a major social impact on racial understanding across the country.

"It made a huge difference," said Grant. "Norman Jewison's films are like that. He knows what he's doing. He's a great filmmaker and a great concept person, and it was a very brave thing to do. But without Sidney … Sidney is a hero. He's a hero."