GARDAI have arrested a 20-year-old female following the death of a young mum Brigid ‘Bernie’ Cash in Blanchardstown.
The woman was known to the victim and is believed to have been socialising in the house with her on the night.
Gardai sources said they are working on the theory that it was an argument between two women.
Ms Cash (20) is originally from Greystones, Co Wicklow.
Her body remains at the scene - a semi-detached home in Warrenstown Walk in Blanchardstown.
Gardaí say there was a social event at the house last night.
Last night three other people were still being questioned at Blanchardstown Garda Station about the events of the night.
The woman who was arrested is being detained at Blanchardstown Garda Station and can be questioned for 24 hours.
Speaking this evening, her mother, who is also called Brigid Cash, said her daughter "was a beautiful looking young girl".
"We are all devastated," Mrs Cash said.
Gardai are appealing to anyone who was either at the party or who may have witnessed anything suspicious to contact Blanchardstown Garda Station on 666 7000 or the Garda Confidential Line 1800 666111