final hours of hated Theresa Riggi

Few will have any sympathy for such a woman but tabloid cliches can never encapsulate a human life. Last week, Riggi died in Rampton Secure Hospital in England, where she had been sent because there were no suitable facilities in Scotland for such a female offender: a risk to herself, and at risk from others, due to her crimes.

She died alone, tormented by paranoia, say medics. In the last hours of her life, the self-proclaimed Catholic ironically reached out to her remaining family.

Chatting on the phone, Riggi had not shown any signs of being overly troubled or distressed, relatives have revealed. No-one suspected what was to happen next.

"When we last spoke on Saturday, there was no indication of any problem," a family statement said. Less than 48 hours later, staff at Rampton found the 49-year-old's lifeless body.

One critical question remains: how did Theresa Riggi die? Initially, there were claims of suicide.

However, the Sunday Herald has learned that Riggi's relatives in Bakersfield, California, have dismissed reports she took her own life, saying she had died of natural causes.

Her siblings said they were told by hospital staff there was "no sign of trauma or suicide" on her body.

It is understood Riggi, who had a history of mental illness, suffered from an eating disorder.

Psychiatrists who examined Riggi said she was suffering from narcissistic, paranoid and histrionic personality disorders - a catalogue of mental health problems that mitigated her murder charge to one of culpable homicide.

Riggi had been moved to Rampton from Cornton Vale, near Stirling, while serving a 16-year sentence for stabbing to death her eight-year-old twins, Austin and Gianluca, and five-year-old daughter Cecilia at the family's Slateford flat in 2010. The killings followed the break-up of her marriage to the children's father.

She tried to cover up the killings with a gas explosion in the second-floor flat before leaping from the window in a suicide bid. She later told officials: "I just want to be with my babies."

More than three years and countless suicide attempts later, her family believe her wish has finally come true - albeit, seemingly not by her own hand.

Relatives released a statement saying Rampton Hospital told them Riggi died of natural causes, adding that they were "devastated and shocked by the news", but said: "We are heartened by the fact she kept her faith through this entire ordeal."

Riggi, maiden name Butimore, is survived by her sister Kathleen and brothers Edward and Paul.

Investigators are still awaiting test results from pathologists. Although mystery surrounds her death, a source close to the family said her body had "given up after all it had been through".

Speaking on behalf of relatives, a Californian priest said: "They feel a sense of relief. They now believe their sister is not being tormented."

Nottinghamshire coroner's office confirmed they are "awaiting test results" and could not yet confirm the cause of death.

Riggi had developed eating problems before she was a mother. One source said anorexia and bulimia "were a concern" and it is understood Riggi continued to have issues with food while behind bars.

She was sent to Rampton because there are no facilities for female high-security psychiatric patients in Scotland and it was felt staff at Rampton were better placed to treat her.

During her incarceration at Cornton Vale, a terrified Riggi was said to spend her time hiding away in her cell. She was reportedly hated by other inmates, who said they would have a party to celebrate her death.

She is believed to have been disfigured after a fellow inmate allegedly slashed her across the face. A 40-year-old woman is currently awaiting trial.

Another inmate pushed her down a flight of stairs. A woman was arrested, but the case dropped due to lack of evidence.

Last year, Riggi was said to be too frail to travel back to Scotland to attend the court proceedings for the attack.

The horrific nature of her crimes made her stand out, even in a prison filled with women used to violence, both as victims and perpetrators.

Her attempted suicide in the moments after the killings failed as her fall was broken by a neighbour. However, she was badly injured, suffering a collapsed lung, a fractured leg and elbow and cuts to her neck and wrist.

While in hospital recovering, the triple child killer was visited by the then leader of the Catholic Church in Scotland, Cardinal Keith O'Brien.

He made the "private pastoral" visit to Riggi while she was being monitored in the Orchard Clinic at the Royal Edinburgh Hospital.

Following her discharge from hospital, she made several more attempts to take her own life.

In Cornton Vale, Riggi is said to have set herself on fire and tried to hang herself with a rope.

She reportedly tried to slit her throat and is believed to have tried to electrocute herself.

If suicide wasn't the final cause of death, then perhaps the series of suicide attempts by a frail woman, still in the grip of a severe eating disorder, finally took a fatal toll on her body.

During Riggi's trial at the High Court in Edinburgh, a picture emerged of an increasingly unstable mother who had been locked in a bitter custody battle with her estranged husband and father of the children, Pasquale, an oil industry executive.

When Pasquale admitted he planned to take the children from her, she snapped. Riggi said she had been left with no choice.

During a phone conversation, she chillingly told him: "Say goodbye then" and hung up. Pasquale never saw his children alive again.

The couple married in 1989, moving from Colorado to England in 1997. Austin and Gianluca were later born in Scotland after Riggi had IVF treatment.

Following the birth of Cecilia, their marriage deteriorated and her husband sought a divorce. While he wanted to remain a part of his children's lives, Riggi reportedly told an acquaintance she wanted "to leave the country for good".

Just weeks before the tragedy, Grampian Police launched a missing persons inquiry when the children's father raised the alarm after the four vanished from their home in Skene, Aberdeenshire in July 2010.

Police, airports and ports were alerted to be on the lookout. The family were eventually traced to Edinburgh on July 21.

An impending hearing scheduled for August 3 tipped Riggi over the edge. She failed to attend court and an order was made for social workers to supervise the children. Tragically, it came too late.

The children's bodies were found lying side by side on a bedroom floor as church service-type music played from a laptop.

After the deaths, the children's father said: "The difficult part, obviously, is seeing constant reminders on a daily basis in front of you - it's playing out in the newspapers and on TV.

"It's almost like it's happening to someone else and you keep asking yourself, 'Is it me, is this my family?'. And then the reality hits you that it is."

Pasquale last saw his children alive on July 4 when he had celebrated Independence Day with them.

He added: "The hardest moment without a doubt was when I first found out. Your life is all about your children, you have plans and you have dreams for them. In one instant, that's gone."

As the bleak facts of the case were relayed out in court, Riggi's defence counsel Donald Findlay told how, at the time of the killings, she was suffering from "an acute stress reaction".

Findlay, one of the country's most experienced QCs, admitted he had never come across a tragedy like this.

He said: "Theresa Riggi is not evil, she is not wicked, she is not a monster.

"If it is possible to love one's children too much, she loved them too much. They were part of her. She was part of them.

"She believed the children and she were safer together in death than they ever could be in life."