An elderly dementia patient who was allegedly bashed by a fellow aged care home resident still can't open his eyes almost one week on from the terrifying ordeal.

John Cain, 87, suffered head and facial injuries so severe he was almost unrecognisable during the alleged attack at HammondCare's aged care facility in Hammondville in Sydney's south-west last Wednesday night.

He was found bloodied and bruised by staff on the veranda outside his cottage, located within the facility's secure dementia care unit.

A fellow resident, aged 67, was arrested the next day and charged with domestic violence-related assault occasioning actual bodily harm.

The man appeared in court on Friday, was granted bail, and has since been relocated to another facility. 

Mr Cain is still recovering in Liverpool Hospital, where he is expected to remain for an extended period.

His daughter Margaret gave 2GB breakfast host Ben Fordham a harrowing update on his condition on Monday.

'Dad is suffering from a brain bleed - he has a fractured eye socket and a burst eardrum, along with defensive wounds to his arm,' she said.

'We anticipate a very lengthy (hospital) visit.'

Disturbing photos showed the battered and bruised pensioner wearing a neck brace in a hospital bed, covered in blood and bruises with both eyes severely swollen and injuries across his head and face.

The update comes just days after Mr Cain's wife of 60 years, Leah, said she feared he may die in hospital.

'It's just a matter now of how long he might live, because he won’t be removed from that hospital,' she told Nine News.

Her husband had been at the HammondCare facility for just six months. 

'I thought he was happy there,' his wife added.

Daughter Margaret said she still has faith in the court system and respects the legal process, despite her father's alleged attacker being granted bail.

'Whatever the court decides will be the correct way forward for this situation and for the resident,' she said.

But the family has demanded answers from HammondCare about the alleged incident and, five days later, Margaret is still waiting for a response.

'There's been nothing,' she said. 

'It's been very traumatic for mum and also my sister, who has flown in from New Zealand to be with her and dad.'

Daily Mail has contacted HammondCare for comment.

The facility confirmed last week that it had launched an investigation into the circumstances surrounding the alleged incident.

It also lodged a serious incident report with the Aged Care Quality and Safety Commissioner.

'We are extremely sorry and deeply saddened that this has occurred,' executive general manager Jenny Summerton said last week.

'Police were notified immediately of the assault and the family were also informed.

'The cottage is one of 30 SDCP cottages nationally that provide specialist care to people with very severe behavioural and psychological symptoms of dementia.

'These are residents assessed as unable to be cared for in mainstream aged care settings.'