Sinn Fein leader Gerry Adams has revealed that his late father emotionally, physically and sexually abused family members over many years.
The shock disclosure followed the Sinn Fein president's call for his brother Liam to give himself up to answer charges of abusing his daughter during her childhood.
Mr Adams said the family, which included 13 children, made the discovery about Gerry Snr in the 1990s.
They received professional help, but the West Belfast MP said he had no recollection of being personally abused.
"He ended up dying a very lonely man where he should have been surrounded by loving family members," he told RTE.
He added it was not the end of the world.
"It obviously tests your faith in humanity when an iconic figure like my father engages in the psychological and emotional and physical and sexual abuse of a child, of his child.
"But with attention, with understanding, with resolve, and with love we can find our way through all of this."
Mr Adams explained why he waited so long to make the troubling revelations.
"I myself for a long time wanted this to be publicised because there is a culture of concealment. But we can only do this when everybody is strong enough to do it.
"And we don't do it for any other reason than as a necessary step in the healing process in our own clan. And also for other families who are in the same predicament, or individuals who just feel this is the end of the world," he said.
He was asked about his father's republican funeral and tricolour on his coffin.
"Personally that was one of the great dilemmas for me because I'm a republican. I'm speaking here as a human being, as a family member," he said.
"I didn't want him buried with the tricolour. I think he besmirched it, but it was a dilemma for other members of my family who felt that they didn't want this at that time out in the open."
Had he not been buried as a former republican activist in the 1930s, a former prisoner, that would have drawn attention to the fact that there was something wrong.
"So you have to look after the living as opposed to the dead," he said.
"I always also had a view that was going to come out at some time."
Liam Adams is wanted by the PSNI over charges of abuse against his daughter over a period of several years during her childhood.
Gerry Adams urged his brother to go to the PSNI for the sake of his niece Aine, who has waived her right to anonymity.
He said he had him "dumped" out of Sinn Fein and, when he heard he was working with youths, reported that to the authorities responsible for the facility.
"Aine (Tyrell, Liam's daughter) needs justice. This has gone on for far too long. And the only way now she can get justice is through the courts," he said.
"And Liam, for her sake especially, for his sake and for the sake of his other children, should do that. He should come forward."