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Robert De Niro gets emotional when talking about the father he is named after, Robert De Niro, Sr., a figurative painter who was also gay.

"To me, he was always a great artist," the acting legend told Out magazine.

Discussing his father's sexuality, the Oscar winner said, "Yeah, he probably was [conflicted about being gay], being from that generation, especially from a small town upstate. I was not aware, much, of it. I wish we had spoken about it much more. My mother didn't want to talk about things in general, and you're not interested when you're a certain age."

Robert De Niro Honors His Late Father in New Documentary

Now 70, De Niro, who has preserved his father's final home and studio in New York City, is opening up about the late painter in a new HBO documentary, "Remembering The Artist: Robert De Niro, Sr."

Though he did not spend a lot of time with his dad, who was divorced from his mother, poet and painter Virginia Holton Admiral, the actor said he was still close to him.

"We were not the type of father and son who played baseball together, as you can surmise," the "Raging Bull" star told Out. "But we had a connection."

He added, "My father wasn't a bad father, or absent. He was absent in some ways. He was very loving. He adored me… as I do my kids."

Robert De Niro on Making 'Grudge Match'

In the documentary, which premieres June 9 on HBO, De Niro recalls memories of his father's despair over his sexuality and his overlooked body of work.

While De Niro was rocketing to Hollywood's top tier, his father was living his final days as a starving artist in Paris.

The documentary is De Niro's attempt to resurrect his father's legacy before it's too late.

"I felt I had to. I felt obligated. It was my responsibility to make a documentary about him," the actor said in the interview. "I should have done this 10 years earlier, but I'm glad I did it now."