Singer and former MEP and presidential candidate Dana Rosemary Scallon broke down in tears in the witness box today, as described being approached by a journalist during the 2011 presidential election campaign about allegations that her brother had sexually abused a girl.
Ms Scallon said the first she heard about allegations made against her brother was during a civil court case in 2008.
She said she was approached by journalist Greg Harkin on Dublin's Grafton Street on 12 October 2011.
Ms Scallon said he asked her what was her opinion of how the Catholic Church had hidden child sexual abuse.
She said before she could answer he said he had sworn testimony from a girl who claimed that Ms Scallon had hidden her alleged sexual abuse by John Brown for over 30 years.
Mr Harkin said the girl's father had claimed in the 2008 civil case that Mr Brown had admitted to him that he had abused the girl for 12 years.
Ms Scallon said she told Mr Harkin she was not able to discuss this court case.
She told the court she was "so shocked" before briefly breaking down.
She also read out a letter sent by Mr Harkin that day, again asking her to comment on the allegations.
She again broke down as she read out that letter.
In the letter, Mr Harkin put it to her that the girl claimed she told her to forgive John Brown as God had forgiven him.
That night, Ms Scallon, told the court she made a statement on RTÉ's Prime Time at the end of the presidential debate in which she criticised the "untrue, malicious and vile" allegations being made against a member of her family.
She cried again as she described that it was "such a terrible day".
On TV3 later she also spoke of "vile and untue" lies.
She said she was being targeted and her brother was collateral damage.
After these interviews, the girl and her mother instituted defamation proceedings against her.
Ms Scallon also read out an email sent to a member of her team a week before the interviews in 2011, which said "the bitch is finally getting what she deserves and the best is yet to come".
At the time she was dealing with false allegations that she had dual citizenship in Ireland and the US and had hidden this when she ran for president in 1997.
Asked by Mr Brown's defence counsel if she had sought to deliberately cover up allegations of sexual abuse made against her brother, for more than 30 years, Ms Scallon said "I have not. I have not" before breaking down in tears again.
Prosecuting lawyers will now begin cross examining her. The defence has finished its evidence in the trial.
This afternoon, Ms Scallon's husband, Damian Scallon, said he "absolutely did not" pray with one of the girls in a telephone call with Dana in the 1970s.
Mr Brown's wife, Patricia, said if she thought her husband was guilty of these allegations, she would not have him living under the same roof as her and her children.
Mr Brown, 60, from Lilly Hill Road, Bracknell in Berkshire, denies five counts of indecently assaulting two girls in the 1970s.
The six men and six women of the jury may begin considering their verdict on Wednesday.