Philip Cairns disappeared on the afternoon of 23 October, 1986 while walking back to school in Rathfarnham.
A documentary on the disappearance of Philip Cairns, a schoolboy who went missing in 1986, is to air on RTE tonight (15 September).
Cairns was a 13-year-old schoolboy who was in attendance at Coláiste Éanna in Dublin, and went missing while on his lunch break.
A large-scale investigation was carried out at the time but no trace of Cairns has ever been found.
His disappearance is among the highest-profile cases in the history of the state, with the investigation resuming in 2016 and DJ Eamonn Cooke being considered a suspect in his disappearance.
Cooke has since died.
The documentary will look at the unsolved disappearance of Cairns, exploring the impact on his family of still not knowing what happened to him after more than 30 years.
It will feature interviews with his family, who discuss what Philip was like as a child, and how it has affected them to this day.
Scannal - Philip Cairns: The Boy Who Never Came Home airs on RTÉ One on Tuesday (September 15) at 7pm.
