Emma Lovell was murdered by a teenager in her front yard. Her ...

For seven months after Emma Lovell's murder, her husband Lee and their two daughters slept in the same room in fear someone would return.

The 41-year-old was stabbed in the heart in front of their house, north of Brisbane, after a violent home invasion just before midnight on Boxing Day, 2022.

The teenager who killed her, and stabbed Lee, had been on a three-day bender when he entered the house armed with a knife.

Paramedics performed heart surgery on the front lawn, but couldn't save Emma's life.

Yesterday, the teen was sentenced to 14 years in jail for what was described by Justice Tom Sullivan as a "particularly heinous" crime.

When Lee saw the teenager in court for the first time, he almost couldn't take his eyes off him.

"You just expected to see a monster, that was my perception, but to see a normal young adult walk in was really bizarre," he said.

Emma and Lee Lovell had been married for two decades.(Facebook: Lee Lovell)

Teen 'somewhat gleeful' discovering unlocked door

Lee and their daughters were in court earlier this month, where distressing vision and audio of the altercation was played.

Footage from security cameras showed the moment the teenager approached the door of the Lovell family home, in North Lakes.

He appeared "somewhat gleeful" when he discovered it was unlocked, prosecutor David Nardone told the court, with footage showing him giving a thumbs up. 

In the black and white vision, the boy could be seen returning to the door with another teenager, who the court heard is his co-accused and is yet to enter a plea on his charges.

This time he returns with a knife and enters the home.

The Lovell's woke to their dogs barking and when they checked their security cameras, they saw their front door was ajar.

Lee opened his bedroom door to be confronted by the teenager and the couple yelled for the intruders to get out.

Medical equipment used to try to save Emma's life was still at the crime scene the next day.(ABC News: Laura Lavelle)

The CCTV footage then shows the teens at the front door, in a violent struggle with the Lovells.

The fight moves into the front yard, where Emma is stabbed in the chest — it is with such force the 11-centimetre blade snaps.

Lee is stabbed twice in the back and kicked repeatedly while on the ground.

The court was silent as they watched the murder. Lee leant forward in his chair — his daughters by his side — looking up to relive his wife's last moments again.

The audio was too much for the family to handle and Lee and his daughters left the court room before it was played. 

Emma Lovell's murder triggered an outpouring of support from the North Lakes community. (ABC News)

The teen was found by police in a nearby house where he told officers, "I’ve got a f***ing alibi". 

However, Emma and Lee's DNA was on the teenager's shoes and under his fingernails, while his fingerprints were found on the couple's bedroom door.

The handle of the knife was found under a lounge chair. 

The court heard the teenager began laughing after he was detained.

Despite efforts to save her life, Emma died in hospital.

Lee Lovell outside his North Lakes home days after Emma's death.(Supplied: Channel 7)

'I don't feel like we will ever stop suffering'

The family had emigrated from England to Australia 11 years earlier, but the distance didn't stop Emma from continuing to care for her mother Marjorie Dowson.

Marjorie told the court through her victim impact statement that Emma's death had "ruined my life".

"I don't know how I am supposed to get over or survive the death of my beautiful daughter," she said.

 Emma Lovell suffered a fatal chest injury and Lee Lovell was wounded in the back.(Facebook: Lee Lovell)

Emma wasn't just Marjorie's daughter, but her best friend. Someone who understood her battle with depression, always calling to check in with her.

"I miss those phone calls as we used to chat and give advice to each other and I still wait for those phone calls every night," Ms Dowson said.

Emma Lovell and Lee had started saving to take their daughters to Italy, where they were married, before her murder.(Supplied)

In what would be her final visit to see Emma, Marjorie made the decision to move to Australia to "make up for the years that we missed".

Emma's brother David Angel described her ability to care for their mum as a "superpower".

"She knew exactly what to say to cheer her up. There is very little that I can say to our mum to help with her pain," he said in his victim impact statement.

"I have tried to be strong and support Lee, my nieces and our mum, but without Emma's superpower I feel I am falling short.

"I don't feel like we will ever stop suffering."

'Too much feelings'

The teen, who cannot be identified because he was 17 at the time of offending, had a "chaotic" upbringing, his defence barrister Scott Lynch told the court.

At just 10-years-old he left his mother's house where he was exposed to violence and excessive use of alcohol.

He went to live with his aunty and uncle, where his mother called him infrequently and never visited.

The only "real nurturing and love" and "stability" experienced by the teen came from his grandmother, however they would only speak on the phone, Mr Lynch told the court.

Her death sent him into a "downward spiral" and during this time he became inseparable with another boy.

The court heard details of the teenager's chaotic upbringing.(ABC News)

Months before Emma's murder, his friend killed himself and the teen discovered his body in the backyard.

His lawyer told the court, the teenager was not someone who could "sit down and talk about his feelings".

All he could say was: "too much feelings", when he was read the victim impact statements.

"He feels extraordinarily sorry for his actions. He regrets every part of that day and that evening," Mr Lynch said.

A candlelight vigil was held in Emma's memory at North Lakes, days after her death.(AAP: Jason O'Brien)

The teenager has a lengthy criminal history with 84 convictions recorded across a period of two-and-a-half years, including the unlawful entry of a premises on 16 occasions.

Mr Lynch told the court there were no previous offences of violence and this was the first time he had entered a house while armed.

He was on a probation order at the time of the offence, with a condition that he attended a 45-minute session a week with a case worker.

However, he received "very little nurturing" during the sessions.

Community's shock sparks calls for action

Lee said he and Emma were "hardworking, law-abiding people" who deserved to "feel safe" in their own home.

"We were an innocent family who did nothing wrong to provoke those involved," he said.

"It was the night after Christmas, a time that is supposed to be our happy time."

(Left to right) Lee, Liz Jones, Judy Lindsay and Michelle Liddle, mother of fatal stabbing victim Angus Beaumont, at a Voice for Victims rally in Brisbane in August last year.(AAP: Darren England)

This sentiment was shared by the North Lakes community in the days after Emma's death.

A GoFundMe campaign raised more than $100,000 for the family.

While an online petition calling for changes to Queensland's youth justice laws attracted more than 150,000 signatures, and Queensland's politicians took notice.

Two months after the murder, the then-premier Annastacia Palaszczuk announced breach of bail would be re-introduced as an offence for young offenders in Queensland.

The community came together at the Wellington Point Recreation Reserve a few days after Emma's murder.(AAP: Russell Freeman)

Lee says he feels "lost in life" without Emma by his side.

"We were more than just a couple, we were best friends who loved spending time together," he said.

Lee says he and his daughters have been dealt a "life sentence".

The sentence was handed down on Lee's birthday and a day after Mother's Day.

"I feel that the girls and I have had our futures robbed from us," he said.

"The holidays that we will never take. Their graduations, weddings and grandchildren — all affected by Emma not being here."

When the judge told the court he found Emma's murder to be particularly heinous, there was a gasp heard from the Lovell's and their supporters. 

Lee said outside court while he was pleased with the outcome, "it is never going to be enough, it is never going to bring her back". 

Under Queensland legislation the maximum time in custody a juvenile can be ordered to serve is 70 per cent of their sentence, unless there are special circumstances.

The teen will be released from custody after serving nine years and nine months.