Sinn Fein leader Gerry Adams said Sunday his late father was a man who emotionally, physically and sexually abused members of his family.
The president of the Irish Republican Army-linked party revealed the abuse as he appealed to his brother, Liam, to surrender to police to face charges that he abused his daughter when she was a child.
Adams told Ireland's RTE broadcaster that he had been struggling to deal with the implications of his brother's alleged actions when he discovered that his father, Gerry Adams Sr., was an abuser.
"I was almost 50 years old and up until that point I thought we were like any other family, with a loving father and so on," Adams said in the interview. "It was a deep shock."
Adams did not go into detail, although he said he had no memory of being victimized. He added that the crimes were "historic" and that those who were abused had not wanted to involve police in the matter.
He said he had long wanted the issue publicized, but said "we can only do this when everybody is strong enough to do it."
"We don't do it for any other reason than as a necessary step in the healing process in our own clan."
The elder Adams was credited with shaping his son's support for violent insurrection in Northern Ireland, but was never a high-ranking figure in the Sinn Fein-IRA movement.
Adams Sr. served an eight-year prison sentence after shooting a Belfast police officer in the foot in a botched IRA operation in 1942. He was interned without trial as an IRA suspect in the early 1970s _ at times sharing prison space with his much more famous son.
He regularly attended public Sinn Fein-IRA rallies in Catholic west Belfast, but he stayed in the background and never spoke officially for the movement.
Liam Adams is wanted by police to answer charges that he abused his daughter, who recently went public with her allegations in a television show aired by Northern Ireland broadcaster UTV.