Still, at least at the start of the interview, he appeared to somewhat miss the point, saying that he wasn't angry with his sister for outing his behavior or publicly referring to him as a monster.
"I'm proud that she was able to finally get to a place that she could relinquish her pain," he said.
While Mo'Nique's parents also appeared on today's show, the actress herself did not participate in any way. She did, however, give her blessing for the sit-down to take place, relaying the message that she hoped her family's story would help other victims of abuse.
As for Imes, he confirmed Mo'Nique's timeline: The abuse began when she was 7 years old and continued until she was 11. Mo'Nique did not tell her parents about it until she was 15, and only then after a violent incident occurred that she—and her brother—still have not revealed.
But while Imes was on the show ostensibly to own up for his behavior, he says he only recently realized how wrong it was.
"I accepted it as being the norm," he said, adding that he was on cocaine, heroin and alcohol at the age of 11, and that he himself had been a victim of abuse.
"The drugs weren't an excuse. They just allowed me and afforded me the opportunity to do the things that were in the back of my mind as a kid that I always wanted to do. Most of the time, the abuse that I did with my sister took place while she was asleep [or] the appearance that she was asleep."
He said his decision to come forward was watching his sister's Academy Award-winning performance in Precious and the all-too-familiar storyline within that film.
Later in life, Imes was convicted of molesting someone else and was sentenced to 12 years in prison. But despite that, he says he and sister eventually made their way back to a normal sibling relationship. At least, until her twin sons were born.
After visiting nephews Jonathan and David in the hospital, he received a phone call from Mo'Nique.
"She said, 'You know what? I don't want you to be around my boys.'" That was the last time he saw his sister.
Meanwhile, Mo'Nique's parents were also present for the airing of the family laundry.
Last year, Mo'Nique told Essence that her parents' reaction to disclosing the abuse was, to say the least, underwhelming, saying that they responded by asking if she was lying and saying that if it was true, it would resurface and then they'd know for sure.
Alice and Steven Imes told Winfrey that they sent away their son to live with his grandmother, but that two weeks later he was back with the family and the behavior was not spoken of again.
Steven defended the family's response by saying the household was in "a total state of confusion" about how to handle itself. Alice added that she was hurt when the family secret went public, but hopes that Mo'Nique's Precious role helped "cleanse her heart."
Neither parent has spoken with Mo'Nique for two and a half years. But that doesn't mean they didn't watch with pride as she racked up award after award.
"I watched in glee," Alice said. "I was happy for her, I was excited for her. I think I was jumping and hollering more than the audience that was there."
As for why Gerald chose now to come forward, he hopes it will help rekindle his relationship with his sister.
"I can only hope by coming forth today, since I couldn't reach out to her, that...somewhere along the line with the apology and the truth of it finally coming out after 37 years, that hopefully somewhere, somehow...we can come back together as brother and sister and say: 'You know what? This happened. I'm sorry that it happened. I'm sorry that it happened to you, and that I was the perpetrator, the one that did it to you. However, I understand your pain. I, too, was there. Now let's share this together and move on.' "