The 24 year old did not speak during the brief hearing.
A man has appeared in court charged with the murders of his siblings in Tallaght, in the early hours of Sunday morning.
18-year-old Lisa Cash, and her eight-year-old twin brother and sister, Christy and Chelsea Cawley, died after they were attacked and stabbed at their family home in Rossfield Avenue, in the Brookfield area.
24 year old Andy Cash, with an address at Rossfield Avenue came before a special sitting of Dublin District Court last night, charged with the murders of 18-year-old Lisa Cash and her eight-year-old twin brother and sister, Christy and Chelsea Cawley.
They were attacked and stabbed at their family home in Rossfield Avenue, in the Brookfield area of Tallaght, in the early hours of Sunday morning.
During the brief hearing last night, Garda Rob Whitty from Tallaght Garda Station, gave evidence of arrest, charge and caution.
Garda Whitty told the court Mr Cash replied 'no comment' when he was charged with the murder of his two sisters and brother.
Judge Patricia McNamara granted the 24 year old free legal aid, and also agreed to a request from his defence solicitor for him to undergo a psychological assessment.
His solicitor Waheed Mudah also asked that the court direct that his client would be kept in solitary confinement, however Judge McNamara said that was a matter for the prison governor.
No application for bail was made and Mr Cash was remanded in custody to appear again via video link at Cloverhill District Court on Friday.