Kerry murder-suicide: Picture emerges of Mossie O'Sullivan's mindset 

Overweight and suffering from a series of issues, including a limp, high blood pressure, and the remnants of a back injury, he is said to have told a small number of friends in July, and again last month, he was undergoing tests.

One of those was a colonoscopy and there is a suggestion locally among friends and acquaintances that the results of that test came through within the past two weeks.

There is even speculation he might have been diagnosed with terminal cancer, although that has not been confirmed.

Gardaí are keen to stress that they have yet to find a motive for what happened but they are keeping an open mind.

This is as they continue their criminal investigation since the discovery of the bodies of Elieen and Jamie at her family cottage at Kilfeighney, near Lixnaw, on Tuesday. 

Mossie's body was discovered nearby.

Their post mortems have been concluded, as has a technical examination of the crime scene. 

“An Garda Síochána is keeping an open mind on all the events leading to the tragic deaths of the O’Sullivan family,” the force said in a statement.

“It remains the case that at this time [that] An Garda Síochána is not looking for any other person in relation to this investigation.

“No motive has yet been established in this case.”

Responding to the gardaí’s ongoing appeal for any information leading up to the tragic events, two of his friends say they have asked gardaí to check his medical records.

They have told other friends of the 63-year-old former truck and bus driver that while it does not explain why he decided to kill his family, they believe this might shed some light on his state of mind.

They say they have also urged gardaí to keep looking for a suicide note, and believe it is either in his car or a workshop in a shed near the house.

A friend of one of the men who say they approached gardaí told the Irish Examiner: “Mossie was a religious note taker. When he was a driver, he used to make meticulous notes of his trips and was always able to say where he was on such and such a date.

I wouldn't say they were diaries as such but he kept notes. He had an attention to detail. His car and his tractor, for example, were always spotless. He looked after his car like a baby.

One of the people he told he was going for tests was a friend he had known for a number of years.

“I last spoke to him around three weeks ago, and he said he had the tests and he was just waiting for the results,” they said, speaking on condition they were not named.

“He was never one to complain and he didn’t exactly go into too many details. But I knew the results were due in the last week or so.

“He didn’t tell me what they were but I did hear back from someone else that the news came back and it wasn’t great. Does that explain why he killed his family? No.

“But his health could give some insight into what was going on inside his head.

“If he was diagnosed as having terminal cancer, and I don’t know that he did, I’ll bet he took it into his head that he didn’t want Jamie to have to look after him or Eileen.”

The tests are understood to have been carried out around the same week as he attended the funeral of his sister-in-law Margaret, wife of one of his two brothers, John.

He is said to have mentioned to a relative his concerns about his health, and the fact that he wasn’t able to manage breeding sheep properly.

A friend who had known him for a number of years said Mossie O’Sullivan “hated” ill health.

“He seemed to have a real problem with it,” they said. “I think it was because he didn’t like the idea of being a burden on anybody.

“Maybe it was also something about not having to go through what he knew others have had to go through. Eileen’s brother had had cancer when he died and Mossie had been involved in helping care for him.

“He used to drive him to Cork University Hospital for treatment. I remember he also took Vincent to the hospital to have his last remaining leg amputated.

“That was a stressful day for all the obvious reasons, but also because the timing belt on his own car went, so he had to get another car, and the timing belt went on that as well.”

One of Eileen’s other brothers, Patrick, who died in 2017, is also understood to have had cancer when he died.

“Mossie was brilliant at helping people out,” the friend said.

“After all, he was devoted to Eileen and was with her constantly during her recovery from a stroke.

He pretty much gave up work to look after her but I think he was always very uncomfortable about death and sickness.

“He’d just keep his head down on that and get on with whatever he had to do for somebody but it wasn’t something he liked to talk about.”

His own issues with health appear to have started about two years ago when he suffered a leg injury after being attacked by a ram.

He had walked with a limp ever since.

He was also involved in a car crash about a year ago, but is not known to have suffered any serious injury.

Whether or not health played any role in this tragedy remains to be seen.

But it is one of the things that has been talked about among a community still stunned by what happened.

Farmer John O’Mahony found Eileen and Jamie on Tuesday evening after he was asked to check up on them by neighbours concerned that the front door of the family home had been left open and there had been no sign of either of them throughout the day.

He told the Irish Examiner how he found them each in their own bed before he called gardaí.

Mossie O’Sullivan himself was found later. He had taken his own life.

Like everybody else, Mr O'Mahony too is baffled as to why O’Sullivan did what he did.

‘It will take a smarter man than me to answer that,” he said.

“I couldn't have a clue.

“I have spoken to the neighbours and they all say the same thing: Of all people, you couldn't expect Mossie to do this and he was mad about Jamie.”