The definitive cause of death of 13-year-old Willie Delaney is still unknown this afternoon, following preliminary post mortem results.
The boy's body, which was buried in a cemetery in Kilkenny more than 30 years ago, was exhumed as part of an investigation into alleged institutional sexual and physical abuse at the Letterfrake industrial school in Connemara.
Inspector Pascal Connolly said that some trauma to the head was identified in the examination of the body but to draw a line between medical and physical trauma was impossible.
Assistant state pathologist Dr Marie Cassidy has taken test tissue back to her laboratories in Dublin for further forensic examination, the results of which are expected over the next few days.
The re- interment of Willie Delaney and his aunt Bridget, who was also exhumed in the examination process, is expected to take place this afternoon at St Kieran’s Cemetery in Kilkenny.
William’s sister Kathleen, who was four when he died, said today the family had suspicions over the cause of his death.
She said: "My mother and father were told he died of meningitis.
"My father never really got over it. He always thought something happened in the institution."
Allegations of physical and sexual abuse at the school first surfaced in 1996, when a man complained to gardai in Dublin that he had been assaulted as a pupil.
An incident room was set up at Clifden Garda station and a team of nine officers assembled under Superintendent Tony Dowd, working on what has become the largest investigation of its kind in the Republic.
Letterfrack, which accepted boys between the ages of six and 16 who had lost their parents, came from broken homes or were deemed to be young offenders, was closed in the mid-1970s.
Files have been sent to the Director of Public Prosecutions, according to officers at Clifden Garda Station, with 15 former members of staff being considered for prosecution.