The High Court has been urged to help a man find out what happened to his infant sister after she was born at St Mary's mother and baby home in Tuam, Co Galway.

Peter Mulryan was described by his solicitor as elderly and "extremely ill" with cancer, the court heard.

His solicitor, Kevin Higgins, said Mr Mulryan, whose infant sister Marian Bridget Mulryan is believed to be among 796 children recorded as having died in Tuam between 1925-61, was too unwell on Monday to be in court. 

Mr Mulryan is extremely anxious to get whatever records exist concerning her.

He wants Tusla to look at the material it has "and see what happened to that little girl, did she die, was she trafficked or is she buried in the pit", Mr Higgins said.

Mr Mulryan (73), Derrymullen, Ballinasloe, wants leave to bring judicial review proceedings against Tusla aimed at getting any material that exists concerning his infant sister, recorded as having died in February 1955 nine months after her birth at the home.

Mr Mulryan went with his mother to the Tuam home in July 1944 and his mother later appeared to have gone to a Magdalene institution and he was "boarded out" at age four.

Tusla has said it has given Mr Mulryan any material it is aware of and has also made the records held by it available to the Commission investigating the Tuam home, which last week confirmed "significant" amounts of human remains were found there.

On Monday, Tusla reiterated it would facilitate inspection by Mr Mulryan of the material in its possession.

Mr Higgins said Mr Mulryan was too unwell to inspect the material on the date offered.  Inspection offers were inadequate and extensive material held by Tusla should be forensically examined and catalogued with any relevant information give to his client.

Mr Justice Richard Humphreys had adjourned the leave application several times to clarify exactly what orders were being sought.

He also directed Tusla to write to the Bon Secours order, which operated the Tuam home, asking if it holds any burial records and, if any records existed at some stage, were they destroyed.

On Monday, Mr Higgins said he considered an April 9, 2013, letter from Sr Marie Ryan, leader of the Bon Secours in Ireland, demonstrated the Congregation knew more about what had happened to children who died there than was indicated in a letter from Sr Ryan of February 15 last.

Mr Higgins said he considered the letters showed Sr Ryan, "as is the norm for the Bon Secours sisters", "is lying through her teeth" and indicated the order knew "a lot more" more in 2013 and knew "where the babies are buried".

The general grave referred to was "the overflow cesspit" of the home wherein lies about 796 young children, he said.

An affidavit from Tusla said it holds records for mother and baby homes in the west since 2011, not 1961, he said.

Following long investigations concerning indemnities to be given, those records were handed over and Tusla "has sat on them", he said.

During exchanges with Mr Higgins, the judge said the grounds for judicial review were "a bit thin".

Mr Higgins said it was "most unfair" to tell him that now, the sixth time the matter was before the court.

The judge said he did not accept that and it was for the solicitor to get his papers in order.

He adjourned the matter for a week to allow Mr Higgins prepare an amended statement of grounds.