Auditors have been called in to look at the records of a crematorium which buried the cremated remains of babies after parents were led to believe there would be no ashes to scatter.
An investigation was launched by Edinburgh City Council last month after it emerged the remains of children who were stillborn or days old were buried in a garden of remembrance at Mortonhall Crematorium without being offered to be returned to parents.
The situation was discovered by child bereavement charity Sands Lothians, which said the council-owned crematorium had carried out the practice for 45 years.
The local authority said families had been offered the remains of their babies from Mortonhall since May 2011.
Councillors have now asked independent auditors from PricewaterhouseCoopers to look through more than 100,000 records at the site.
Lesley Hinds, the local authority's environment convener, said: "A key issue being raised by parents is the need for an independent role in the investigation, so a completely separate audit of the crematorium records is now being carried out.
"There are over 100,000 documents relating to cremations and the audit will have a particular focus on those involving babies.
"This is intended to provide us with comprehensive information from which we will endeavour to deal with the questions and concerns of families, and develop an understanding of what has happened at Mortonhall."
Ms Hinds said the council investigation into the historic and current practices at the crematorium are to be discussed at a committee meeting next week.
She added: "The report will address key areas of concern and set out what lessons can be learnt for the future. We will carry on working closely with Sands as the investigation progresses and will continue discussions over some form of permanent memorial. We hope to consult widely on this soon."