Lyle and Erik Menendez have more than a friend in comedian Rosie O'Donnell. They have a "big sister."

O'Donnell is speaking out about how she's championed the brothers, who are currently locked behind bars in San Diego serving life sentences without the possibility of parole in the murders of their parents, Jose and Mary "Kitty" Menendez.

The men have seen a resurgence in their story thanks to documentaries and television series being made about them, most recently Netflix's "Monsters: The Lyle and Erik Menendez Story," which both brothers have condemned.

LYLE MENENDEZ, WHO SHOTGUNNED PARENTS TO DEATH WITH BROTHER, PLANS FOR LIFE AFTER PRISON AMID NEW APPEAL

Lyle Menendez in a blue sweater and Kyle Menendez in a coral sweater sit with attorney Leslie Abramson, both putting hands to their mouths and chin

Erik Menendez and his brother Lyle are photographed in 1991 alongside attorney Leslie Abramson. (Mike Nelson/AFP via Getty Images)

O'Donnell says their history is complex. 

"I was out to lunch with Barbara Walters and our publicist Cindy Berger, and I said, ‘Barbara, you’re not going to believe this, but guess who wrote to me – Lyle Menendez," O’Donnell told Variety. "Barbara said, ‘Ignore him, he’s a murderer. He’s very cunning.’"

In 1996, Walters famously interviewed both Lyle and Erik in prison.

O'Donnell admittedly didn't respond, only entering the brothers' lives two years ago after watching a documentary that included new evidence that supported Lyle and Erik's story; they'd been molested by their father. O'Donnell spoke out on social media, and from there, a relationship was born.

"I got a call from Lyle’s wife – I didn’t even know he had a wife – asking if I would talk to him," O’Donnell explained. "He called me on Mother’s Day last year."

Rosie O'Donnell in a denim jacket smiles wearing circular black glasses on the carpet

Rosie O'Donnell says many years prior to forging a relationship with the Menendez brothers, she ignored a letter from Lyle due to Barbara Walter's warning. (Olivia Wong/Getty Images)

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Since then, O'Donnell and the brothers have established a friendship of sorts, one that the former talk show host describes as almost familial.

"I feel like a big sister in a way. Lyle is one of the most lauded prisoners in the California prison system. You can’t ignore that. If he was sort of the psycho who was screaming at everyone and a maniac, would he have done hospice for the dying prisoners? Would he have done all of the things that he did that allowed him to finally get moved from San Francisco down to his brother because he had 10 years straight without one infraction? Nobody can mask their mental illness that much in 35 years. To be the extraordinary inmates that they both are is pretty damning testimony as well."

She met Lyle for the first time last year, greeting the elder Menendez brother with a hug. "Then Erik came over to me, hugged me, and whispered in my ear, ‘Thank you for loving my brother.’ It was very, very moving to me."

Lyle Menendez looks pensive in court holding two fingers up to his cheek

Lyle Menendez is photographed in court. (Kim Kulish/Sygma via Getty Images)

"I feel like a big sister in a way."

— Rosie O'Donnell

O'Donnell said that she and Lyle "talk a lot."

"I told them I would do what I could with whatever dwindling fame I have to bring light to their story. I said, ‘It’s not the 90s, Lyle. I’m not on that show anymore,’" referencing her talk show that ended in 2002.

Rosie O'Donnell in a black suit puts her hands up as she hosts her talk show "The Rosie O'Donnell Show"

"The Rosie O'Donnell Show" aired from 1996 to 2002. (Frank Micelotta/Getty Images)

"I think if you feel strongly about something and you want to try to help society, you can use your voice because the children who are abused in their homes don’t have a voice. It’s up to the adults who were once those children to speak for them."

The brothers have the potential to be resentenced, or even released, in light of new evidence being reviewed by George Gascón, the Los Angeles County district attorney, which he announced last week.

O'Donnell said she was privy to the groundbreaking decision before the media.

A bald Lyle smiles and Erik Menendez smirks in mugshots taken in 2023

The Menendez brothers are both serving time in the Richard J. Donovan Correctional Facility. These mugshots were taken of Lyle, left, and Erik in 2023. (California Department of Corrections)

"I told them I would do what I could with whatever dwindling fame I have to bring light to their story. I said, ‘It’s not the 90s, Lyle. I’m not on that show anymore.'"

— Rosie O'Donnell

"As soon as the news dropped, I sent them a text and said, ‘It’s really happening. Now, put that smile on your face. Here we go.’ This is what they’ve been waiting for for so many decades, and it’s about time. I think that we, as a society, it’s time that we said, ‘We made a mistake, and we didn’t understand what we understand today.’ It’s kind of a miracle, but so deserving. I’m so thrilled for them."

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"They’re excited," she continued. "They’re happy. I came in two years ago as a cheerleader. I told them then, ‘You’re going to get out of there.’ They didn’t really believe me, but I believe that the wrong will be righted. They’re still reticent to believe it’s going to happen."

Erik and Lyle Menendez lean back to say something to the other in court behind their attorney

Erik and Lyle Menendez could potentially be released soon. (Kim Kulish/AFP via Getty Images)

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O'Donnell already has plans set up with Lyle if he is indeed released. 

"I’ve always told Lyle that I will take him to Nobu because he thinks that’s the place to go," she said of the luxury-chain Japanese-Peruvian restaurant frequented by celebrities. "Sometimes, I would talk to him at night, and I’d say that my friends and I went to Nobu for lunch. I’d say, ‘Buddy, when you get out, I’ll take you to Nobu.’ When I talked to him the other day, he said, ‘When are we going to Nobu?’ I said, ‘Sooner than you think.’"