Oliver Huxley is a haunted man. With heavy shoulders and an ashen face, Mr Huxley spoke of a life spent in his darkened apartment, fearful of strangers and having visions about the night his brother Morgan was murdered as he lay in bed.

"I see Morgan waking up ... and trying to stop the dark figure ... on top of him.

"I see Morgan's strong arms trying to fend off what he can't see. I see Morgan covered in blood, trying to breathe.

"I see Morgan crying and screaming. Inside he's so confused, he must have thought he was dreaming."

Mr Huxley was sitting in the NSW Supreme Court about two metres from his brother's killer, Daniel Jack Kelsall, who will find out later on Wednesday whether he will spend the rest of his life behind bars.

On March 18, a jury quickly found Kelsall, 22, guilty of the stabbing murder of the 31-year-old marine mechanic.

The Crown's case was that Kelsall followed Mr Huxley from the Oaks Hotel in Neutral Bay into his Watson Street flat, where he indecently assaulted him and stabbed him more than 20 times in the early hours of September 8, 2013.

Mr Huxley's sister Tiffany, mother Deirdre, and father Allan also gave victim impact statements to the court, speaking of their grief-stricken lives.

Tiffany Huxley said Kelsall's trial had been a nightmare, and the details of her brother's death left her traumatised and angry.

"My family and I had to sit there in silence, as Morgan's killer told his calculated lies to the court.

"For some strange reason, there was a small part of me that was hoping once the trial was over, Morgan would come back to me.

"Little did I realise how much further I would fall into pain and depression after the trial was finished and Morgan was still gone."

Crown prosecutor Peter McGrath, SC, said there was no psychiatric disorder that explained or excused Kelsall's actions, and he called for a life sentence to be imposed.

Mr McGrath said Kelsall was "callous" and "cold" in going home to his parents' apartment after the stabbing, as though nothing had happened.

"He feigned surprise and concern about the fact there had been a murder."

Mr McGrath said a psychiatrist found Kelsall most likely had a personality disorder, with psychopathic traits.

Defence barrister Christopher Watson acknowledged that Kelsall had not shown any remorse or contrition, but said his risk of reoffending was difficult to assess because of his youth.

Justice Robert Allan Hulme will sentence Kelsall at 2pm.