Seven-year-old Chelsea Sinnott remains in a stable condition at Wexford General Hospital following a car crash which killed her sister Tanya (19 months), her brother Trevor (four) and her mother Jacinta (24).
A front-seat passenger, Lee Murphy (17), was transferred to St James's Hospital in Dublin, where he is said to be "in a critical condition".
The children's father no longer resides in Wexford.
The family is from Holdmanhill, Duncormick, Co Wexford. Local priest Fr Gerald O'Leary said counsellors were called in to St Joseph's national school yesterday to comfort children.
Chelsea is a pupil at the school and Trevor joined junior infants last month.
Fr O'Leary said the community was "shocked and stunned" by the tragedy and that Ms Sinnott's parents were already trying to come to terms with the loss of their son Gary (19), who died following a single-vehicle crash at Wellingtonbridge, Co Wexford, in May.
Ms Sinnott is also survived by an older brother and a younger sister.
Ms Sinnott's 1995 Nissan Pulsar Hatchback car was crushed after it collided with an articulated truck at Larkin's Cross, about five kilometres outside Wexford on Wednesday evening at about 8.30pm.
The driver of the truck was not injured but was treated for shock. The emergency services had to use cutting equipment to remove the victims from the car.
Supt John Roche of Wexford Garda station, who is leading the investigation into the crash, described the scene as "traumatic" and said "it was heart-rending to watch as the body of a young mother was put into one ambulance and the bodies of her two dead children were put into another".
Supt Roche added: "This is the reality of the carnage on our roads".
Fr Seán Gorman, parish priest of the nearby village of Taghmon, said he had anointed and administered the Last Rites to Ms Sinnott and her two children who were pronounced dead at the scene. Their bodies were taken to Waterford Regional Hospital yesterday for postmortem examinations.
They will be buried together on Sunday morning after a funeral Mass.
Ms Sinnott had been driving from the Taghmon road, the R738 on to the busy N25 when her car collided with the truck, which was carrying a load of steel and travelling towards New Ross.
The N25 between Wexford and New Ross is part of the national primary route between Rosslare and Cork.
Adrian Doyle, director of Services for Wexford County Council said that the road at Larkin's Cross was "narrowed last year and a filter lane removed for the purpose of improving safety".
Although there has been a number of accidents and fatalities on the N25, gardaí say that this is the first fatal accident at Larkin's Cross.
George Donovan, who lives at nearby Barntown and uses the road every day, said that the busy junction "would benefit from overhead lighting and a speed restriction".
The section of the road where the collision occurred has a speed limit of 100km per hour although trucks are limited to 80km per hour.
The road was closed yesterday as the Garda's divisional forensic collision investigation team combed the debris-littered surface.
A helicopter from the air support unit took pictures of the scene. Weeping friends and relatives arrived to place fresh flowers on the verge.
Both the car and the Mercedes Benz truck, which is operated by Nolan Transport of New Ross, were later removed to the Garda compound at Wexford for further technical examination.
The truck driver yesterday voluntarily attended Wexford Garda station to provide an account of the collision. The man, who has not been named, is a Polish national living in the New Ross area.
As he does not speak English, an interpreter was provided.
The tachograph of the truck was removed for a routine examination.
