The sister of missing schoolboy Philip Cairns has said a recent social media campaign about his disappearance has been shocking and deeply distressing to her family.

Sandra Cairns was speaking at an event to mark Missing Persons Day.

She said it has been 30 years since her brother went missing while returning to school in Rathfarnham.

Ms Cairns said over the years her family has received great support from the local community and they have been moved by the kindness, empathy and generosity of people.

She said there has been much speculation about what happened to her brother over the years but a recent social media campaign "has been shocking and deeply distressing".

Meanwhile, the father of a 22-year-old man who disappeared 16 years ago on a night out in Dublin has said he still has not given up hope.

Trevor Deely from Naas in Co Kildare, went missing on 8 December 2000.

He was last seen on Haddington Road in Dublin 4 and in the Leeson Street/Baggot Street area in the early hours of that morning having earlier attended a Christmas office party.

No trace of him has ever been found.

At the event in Farmleigh in Dublin today, his father Michael said he still had not given up hope with the 16th anniversary of his son's disappearance tomorrow.

Gardaí have opened a new investigation into the disappearance.