Gardai believe people who were children when Philip Cairns disappeared in October 1986 may have information on his schoolbag.
The Dublin schoolboy's been missing for almost 30 years, but new information has been given to gardai in recent months.
One of the many lines of inquiry is that convicted paedophile Eamon Cooke was involved in the death of the 13 year old.
Philip Cairns was on his way back to school in Rathfarnham when he disappeared without a trace. But his schoolbag turned up days later in a nearby lane, and Gardai now believe that bag could move the case along.
Superintendent Peter Duff is with Tallaght Garda Station.
A woman came forward after the 25 year appeal for information, Gardai say her statement has opened up 160 lines of inquiry, among them, that convicted paedophile Eamon Cooke was involved.
Superintendent Duff says his death earlier this month may enable witnesses to come forward now.
