The sister and niece of Dana Rosemary Scallon have begun proceedings against the failed presidential candidate and TV3.
The plenary summons, which was served last Friday evening, follows a controversial interview which Dana gave to TV3's political editor Ursula Halligan in which she made a number of allegations.
Lawyers for Susan Gorrell and Susan Stein, the niece and sister of Dana, say they are now acting with a view to getting the case into the High Court as early as May.
Ms Gorrell alleges that her uncle John Brown -- who had been involved in Dana's campaign -- abused her on a number of occasions between the ages of 5 and 13.
The allegations came to light when Dana stunned fellow candidates on the RTE presidential debate by launching an emotional attack on what she called "vile" allegations made against her family. At the time she said: "It has come to my attention that yet further allegations -- this time of a most untrue and malicious vile nature -- have been levelled against a member of my family".
She repeated this sentiment during a later interview on TV3 with Ursula Halligan.
Just two hours before TV3 broadcast the interview, US lawyers for Ms Gorrell sent a warning to the broadcaster, stating that their client stood over the allegations and that legal action would be taken if the interview went ahead.
Despite the warning, the station took the decision to air the interview -- and placed an extended version on the TV3 website, which to date remains online.
Following the controversy, Mr Brown removed himself from his sister's campaign. He is currently understood to be residing in London.
The former MEP's failed bid for the Aras was dogged by controversy, including claims that somebody may have been trying to kill her.
Experts said afterwards that a late-night blowout on her car was most likely caused by a simple puncture.
The girl at the centre of the sex abuse allegations that rocked Dana's presidential campaign is now a 42-year-old film producer.
Ms Gorrell is a leading figure in the film business in Iowa and is co-owner of Rell Productions.
In 2009, she co-produced A Million Spokes, the award-winning documentary on a seven-day bike ride across Iowa, with her husband, Ken Gorrell. Mr Gorrell previously won an Emmy in 2008 for his work on the HBO mini-series John Adams.
TV3 has stated it will be giving no comment at this time.