They were the sons of a football-mad father of proud Maori heritage living on the Gold Coast who wanted his kids "to strive for the stars".

Brothers Lionel and Nelson Patea were the younger cousins of singer and Australian Idol contestant Ricki-Lee Coulter who spent their early years in Whanganui.

Their father Andrae had the motto "live life 'cause life matters" and organised an annual Waitangi Day for Gold Coast Kiwis as a "staunch believer in giving back to the community".

But the dreams Andrae Patea had for his sons are now in tatters.

The brothers are convicted killers now both in Queensland prisons in opposite corners of the state.

They met in the Brisbane Supreme Court on Monday and laughed before pleading guilty with their cousin Aaron Crawford to killing Gold Coast pool builder Greg Dufty in July 2015.

The father-of-two was bludgeoned to death with a shift spanner and tyre iron by Lionel Patea, and his body dumped and set on fire by Crawford and another man who were high on ice.

As Mr Dufty's former partner Sharni Mill wept in court, the Patea brothers joked with each other in the dock.

Nelson Patea, 24, and Aaron Crawford pleaded guilty to manslaughter, Crawford also pleading to interfering with a corpse, Lionel pleading to murder.

Lionel Patea, 27, smiled as he stood and said "guilty" in a bored tone.

When asked if there any reason why a sentence should not be passed on him, he replied: "Nah."

It was the second time the once talented rugby league player turned Bandido bikies enforcer had pleaded guilty to murder to prevent a trial from proceeding.

The last time was in February last year to the brutal killing of his former girlfriend and the mother of his young daughter.

Two months after murdering Dufty, Lionel Patea began terrorising Tara Brown over custody of their daughter and her seeing other men.

After eight days of fear during which he held scissors to her neck, Tara dropped off her daughter at kindergarten and was chased by Patea in his 4WD.

The chase reached speeds of 100km/h before Patea rammed Tara's vehicle, forcing it off the road.

He then went to the wreckage carrying a steel fire hydrant and beat Tara 16 times, causing devastating brain injuries.

Tara Brown died after her life support was switched off on September 9, 2015.

Since being sentenced to life in prison, Patea has brawled with other prisoners.

His boiling water attack on another inmate he believed to be a paedophile resulted in him being moved to Lotus Glen Correctional Centre in far north Queensland.

His longtime lawyer Campbell MacCallum has already said that Lionel had significant mental health problems which had seen his decline in a segregation wing in jail.

Lionel and Nelson's father Andrae and mother Vanessa are believed to have been in the Brisbane Supreme Court to hear their sons admit to being killers.

Just over a decade ago the couple were bringing up their sons, then aged 16 and 13, as the boys attended Keebra Park State High School.

Though born in Victoria, Lionel spent his early years with his family in the New Zealand town of Whanganui before moving to the Gold Coast where the brothers lived for sport.

Lionel played rugby league for the Benowa Under 17s, and Nelson for the Coombabah Under 15s.

Lionel was the more talented player and made the South Coast Maori Rugby League.

His father Andrae was member and fundraiser for the Nerang Rugby Union Club.

The Pateas lived in a modest house in the inland Gold Coast suburb of Arundel with their maltese terrier and Shi Tzu dogs, watched a lot of sport and mixed with other local Kiwi families.

The boys' older sister Jessica was already at Griffith University, and was friends with a younger Tara Brown, her brother Lionel's high school sweetheart.

Lionel had already begun to show signs of mental instability, reportedly self harming when rejected by a romantic interest.

He had also been bullied in the schoolground about his Maori heritage.

In 2009 aged 18, Lionel finished school and immediately became involved with a "baby bikie" gang, the Mexican Soldiers.

The Soldiers and the Gold Coast Brotherhood were feeder gangs, respectively to the Bandidos and the Nomads.

The Gold Coast Bulletin reported that Lionel became a standover man and drug runner.

He began to assemble a criminal record, and in 2010, as he became a Bandido gang prospect, he had racked up four matters.

He was fined for public nuisance, was convicted of unlawful possession of suspected stolen property, and of breaching a domestic violence and of wilful damage.

Lionel was by now a Bandido gang drug dealer and admired with in the gang as a violent operator and enforcer.

He was elected the gang's Gold Coast chapter sergeant-at-arms and in 2011 received six months prison for fraud, unlawful use of a motor vehicle and driving without a licence.

The sentence was immediately suspended and he served no time behind bars.

Patea and Tara Brown had an ongoing, if rocky relationship and by late 2011 she was pregnant with their daughter.

But their relationship was marred by Lionel's violence to Tara.

Two months after the birth of their daughter in May 2012, police took out a permanent AVO protecting Tara against Lionel.

He breached it by telephoning Tara and threatening her, and was ordered to prison for one month.

On the night of September 27, 2013, the infamous Gold Coast bikie riot between the Bandidos and rival gang the Finks broke out at Broadbeach's Aura Tapas and Lounge Bar.

Police later described Patea as a "key player", and he would go on to plead guilty to public nuisance and cop a $2500 fine.

In July 2014 Lionel Patea and Tara Brown decided to renew their relationship.

Their daughter was almost two years old and Patea was quitting the Bandidos, as stringent bikie laws were mooted in the wake of the riot.

He was giving up a rumoured $250,000-a-year salary with the gang based on his powers to extort money, but police were coming down heavily on Gold Coast bikies.

Patea went to Gladstone to work in the mines.

Facebook photos from the time show happy daddy and daughter shots and affectionate posts from Patea to Tara.

Patea, however, was still connected to the Gold Coast drug trade.

His cousin Aaron Crawford was growing cannabis on the Gold Coast with a partner, Greg Dufty.

Mr Dufty, whose pool building business was virtually non-existent, would run the drugs up to Darwin.

In the middle of 2015, half of one cannabis crop worth about $32,000 went missing. Crawford called on Lionel and Nelson Patea and two other men, Clinton Stockman and Liam Bliss to question Mr Dufty about the drug's whereabouts.

On July 6, 2015, Crawford lured Mr Dufty to isolated Mt Nathan in the Gold Coast hinterland on the promise of a drug deal.

Lionel Patea was lying in wait with a shifting spanner, a tyre iron and a knife and emerged to assault Mr Dufty.

The next day he phoned one of the men to ask if Mr Dufty had come clean on the drugs and was informed that the 37-year-old had died from the beating.

Crawford and Stockman disposed of Mr Dufty's body the next day, burning it while both high on ice.

The following month, Lionel Patea and Tara Brown flew to New Zealand for a holiday.

At Auckland Airport, they had a massive argument about her past boyfriends and according to the Gold Coast Bulletin "he had massive jealousy issues and he couldn't handle it".

When they returned to the Gold Coast, Tara tried to organised visiting rights for Patea with their daughter, but the couple fought both verbally and through their lawyers.

She escaped for a day to a refuge but found it dirty and occupied by drug addicts, and returned.

On September 8, 2015, Tara dropped her daughter at a Gold Coast kindergarten and when she pulled back out onto the road, Patea was following her in his black 4WD.

He cut off her car, forcing her to stop and then got out with a knife. and began punching her driver's side window.

Tara took off and Patea chased, both vehicles reaching speeds of 100km/h.

Tara took off down a side road, Patea in pursuit until he rammed her car knocking it over an embankment.

While she was trapped in the wreckage, he beat her with the 7.8kg steel fire hydrant before fleeing the scene.

Patea turned himself into police with self-inflicted stab wounds and a collapsed lung, saying he did not remember anything.

For Dufty's death, Lionel Patea, Nelson Patea and Aaron Crawford await sentencing.

In February, Liam Bliss and Clinton Stockman, pleaded guilty to manslaughter.

Mr MacCallum told the Gold Coast Bulletin that his client, Lionel Patea, has significantly deteriorated in prison.

"I've never seen a violent side of him. He and his brother are polite, well mannered, respectful and engaging in any dealings I've had with them," Mr MacCallum said.

"I completely appreciate the absolute horror of what Lionel did and I feel complete compassion and sadness for Tara's family.

"Lionel has had significant psychological and psychiatric issues since pre-puberty.

"The last conversation I had with Lionel after he was sentenced, he seemed relieved.

"He intends to try to study some courses. He wants to rehabilitate himself so he can at least behave in society."

If you're in danger now:

• Phone the police on 111 or ask neighbours of friends to ring for you.

• Run outside and head for where there are other people.

• Scream for help so that your neighbours can hear you.

• Take the children with you.

• Don't stop to get anything else.

• If you are being abused, remember it's not your fault. Violence is never okay

Where to go for help or more information:

• Women's Refuge: Free national crisis line operates 24/7 - 0800 refuge or 0800 733 843 www.womensrefuge.org.nz

• Shine, free national helpline 9am- 11pm every day - 0508 744 633 www.2shine.org.nz

• It's Not Ok: Information line 0800 456 450 www.areyouok.org.nz

• Shakti: Providing specialist cultural services for African, Asian and middle eastern women and their children. Crisis line 24/7 0800 742 584

• Ministry of Justice: www.justice.govt.nz/family-justice/domestic-violence

• National Network of Stopping Violence: www.nnsvs.org.nz

• White Ribbon: Aiming to eliminate men's violence towards women, focusing this year on sexual violence and the issue of consent. www.whiteribbon.org.nz