Robert De Niro said in a recent interview that his late father never discussed his homosexuality.
"He was very private so he wouldn't go into that with me," De Niro told Katie Couric on Yahoo News. "I don't really know much about that side of my father."
The Academy Award winning actor said he did have "some inkling" that his father was gay and his mother even made some inferences but it was never "brought up."
"You kind of ... knew but didn't know," he said.
De Niro has been making media rounds to promote his documentary, "Remembering the Artist: Robert De Niro, Sr." The actor used his father's journal entries to chronicle the life of the artist, who died of prostate cancer at 71 years old in 1993.
In the documentary, De Niro Jr. reads several journal entries where his father describes his struggle with homosexuality.
"If God doesn't want me to be a homosexual (about which I have so much guilt) he will find a woman whom I will love and who will love me or at least create an interest in me in women as sexual partners," De Niro Sr. wrote.
"The pills don't help or the prayers either. God! God! God!"
In another journal entry, De Niro Sr. – whose paintings include depictions of Jesus and the cross – wrote, "Being a painter is an affliction. Like being a homosexual. One has to have the strength to continue working without the recognition either before or after death just as one had to have the strength to accept life alone without the thought of romantic attachment."
The younger De Niro, who wants to promote his father's art work, said his parents divorced when he was 11 or 12 but actually separated when he was 2 or 3 years old.
"Obviously, I realize now that it was hard for him," the actor said.