A pregnant woman who died in a horrific apartment fire was "excited" after finding out that she was expecting her first son, a close friend has revealed.
Annemarie O'Brien (27), who was seven months pregnant, died along with her daughter Paris (2) in the fire at Cluainin Cronan, Kilcronan Avenue, Clondalkin, at around 2.30am yesterday.
Her cousin Biddy O'Brien's daughter Holly (3) was also pronounced dead yesterday morning and Biddy's son Jordan (4) died from his injuries in the afternoon.
Biddy was fighting for her life last night at St James' Hospital.
Gardai have launched an investigation into the cause of the fire.
The initial indications are that it was caused by an electrical or wiring fault linked to the TV or the area close to the appliance.
Joanne Moorehouse, who is a cousin of Biddy O'Brien, told the Herald of the families' devastation.
Ms Moorehouse, who was also close friends with Annemarie, said the mum-to-be was looking forward to having a baby boy which was due before the summer.
"We are both pregnant and I only bumped into Annemarie in Holles Street on Tuesday," said Joanne.
"She told me she was expecting a boy and was really excited. She said she was looking for a house to bring up Paris and the new baby in and was in Clondalkin hoping that housing would come through for her soon.
"We're all devastated. We just want to know what happened."
It is believed that Biddy had been visiting her cousin with Holly and Jordan when the tragedy struck.
Biddy lives in Aughamore Lane, Shankill, where devastated neighbours and loved ones were last night trying to come to terms with the tragedy.
Parish priest of Shankill Fr John O'Connor said the community would rally to support the victims' families.
"I don't think there's really any words that could respond to this awful tragedy," he told the Herald.
"I think it's absolutely awful. I was speaking to the dad of the two children earlier today and it's just so sad.
"His wife [Biddy] is still in hospital and in a bad way and we can only pray that the Lord will spare her. The loss of three children is just shocking.
"I married that couple and my heart bleeds for them. They're very good and caring people and will be missed terribly.
"All we can do is put everything in God's hands and to console those who are bereaved."
It has also emerged that this is the second fire tragedy to hit Annemarie's family.
Her brother Andy O'Brien, who was 20 at the time, died in a container fire in Bray in 2011.
Andy's remains were found in a prefab to the rear of the local church on the morning of January 25, 2011.
At the time of her brother's death, Annemarie wrote a message of tribute to him on Facebook.
"Love you Andy," she wrote. "Sleep tight bro. Thinking of you always. Miss u more than anyone could imagine. RIP."
Originally from the Fassaroe area of Bray, Andy had been sleeping away from home for a number of nights, at several locations, including the place where he ultimately lost his life.
The shed in the church grounds was often used as a shelter for people with nowhere else to go.
At the scene of yesterday's fire Garda Inspector Ken McLaughlin, of Clondalkin Garda Station, said officers and Dublin Fire Brigade would carry out a full investigation.
He confirmed that all five people caught up in the fire were in the one apartment at the time of the incident. A full technical examination is due to take place.
"We're at the scene of a terrible tragedy and I would like to express our sincere sympathies for the families of those that are involved in this incident," he said.
"At the moment we're keeping an open mind on the incident."
Gardai are appealing for witnesses to call Clondalkin Garda Station on 01-666 7600, the Garda Confidential Line 1800 666 111 or any Garda station.
Yesterday Taoiseach Enda Kenny issued a message of condolence to the victims.
"I want to tender our sympathy on the death of a young mother and three children who lost their lives from smoke inhalation in a fire early this morning and to the others who have been injured," he said.
Children's Minister Katherine Zappone said her thoughts and prayers were with all those affected by the horrific incident.
Sinn Fein TD Eoin O Broin said in a statement: "My thoughts are with the bereaved families, friends, and members of this tight-knit local community this morning.
"The death of three young children and a young woman is a tragedy and the people here in Kilcronan are numb with shock and sadness at this devastating loss of life.
"My thoughts are also with those seriously injured in the fire who are being cared for in hospital."