The father of a then 15 year-old boy, who attempted to murder a young woman in Dublin in 2017, says no one should have to go through the trauma she suffered.
He's been giving evidence at the re-sentencing of his son, after the Court of Appeal ruled the initial 11 year detention was too lenient.
The boy, who is now 17, pleaded guilty to the attempted murder of Stephanie Ng in Dún Laoghaire two days before Christmas.
After suggesting they take a selfie, he grabbed her from behind, choked her, before slashing her neck and leaving her on the seafront.
The boy's father told the court from primary school his son exhibited some disturbing signs.
When he was 14 he told him he couldn't go to school as he had a voice in his head telling him violent things and he might attack another child.
When gardaí came to arrest the boy, his father said he was surprised but knew it was true.
He said his son has been in Oberstown for 2 and a half years and is much better.
His treatment is going well and he's completed his junior and leaving cert.
His father said he regrets not having a drug to stop his hallucinations earlier, and that his son was so manic at the end, he wished he hadn’t allowed him to have such a high dose of antidepressants.
The court will give its decision on re-sentencing tomorrow.
