The Catholic religious order at the centre of the St Patrick's Guild baby mix-up scandal has claimed it cannot shed any light on the matter.
The Religious Sisters of Charity broke its silence on the case last night, telling the Irish Independent any nuns who would have been involved are now dead.
Helen Maguire (71) gave her newborn baby to nuns at St Patrick's for safekeeping in 1966. But DNA tests have revealed the baby the nuns gave her back is not her biological daughter.
The discovery has devastated Ms Maguire and the child she raised, Christine Skipsey (52).
Both have been searching for answers since receiving the results last July. A key question is whether the mix-up was accidental or intentional, but the quest for the truth will be hampered by the fact those involved are no longer alive.
In a statement, the order said it took over the management of St Patrick's in Blackrock, Co Dublin, in 1943. "In May 2016 all adoption records held at St Patrick's Guild were passed over to Tusla," it said.
"There are no sisters alive today who would have been involved there and all enquiries should be made to Tusla or the Adoption Authority."
The order was asked whether it knew of any other cases where babies were swapped.
It was also asked how many unmarried mothers may have been referred to St Patrick's by 'singing priest' Fr Michael Cleary. However, these questions were not addressed in the statement.
Tusla has been providing assistance to Ms Maguire and Ms Skipsey in recent months.
According to Ms Maguire, the child and family agency believes it has identified her biological daughter. Arrangements have been put in place for them to meet in the near future. It is believed her birth daughter was adopted by a married couple in Dublin.
Originally from New Inn, Co Tipperary, Ms Maguire became pregnant while working in Dublin at the age of 18.
She travelled to London and gave birth there in November 1966. This was initially kept secret from her parents as she feared her father would force her to have the baby adopted.
Ms Maguire said that when she needed somewhere to leave the baby temporarily while visiting her parents the following month, Fr Cleary suggested St Patrick's.
Fr Cleary was a chaplain to the Irish community in London at the time. Ms Maguire said the priest believed she would give the baby up for adoption, but she refused to sign papers presented to her by the nuns. An intake form noted her intention to keep the baby and this was further confirmed in a letter from Ms Maguire to the guild.
When she returned to collect her daughter after six weeks, Ms Maguire was briefly suspicious. The baby she gave birth to had dark hair, but the child she was presented with had blonde hair. She said the nuns reassured her that all children were born with dark hair and the baby was hers.
Ms Maguire and Ms Skipsey are expected to issue legal proceedings against the society, which is in voluntary liquidation. St Patrick's is also set to face other legal cases over the false registration of births.