A void that can't be filled

Son to be sentenced on June 2 for murdering his mum

“We are not the same people we once were.”

Those words from Annie Heyneman’s devastated children echoed through the Central Criminal Court as details emerged of how the Cavan mother died, stabbed at least 14 times by her own son in a frenzied knife attack that also left her husband fighting for his life.

Danny Heyneman (32) has pleaded guilty to the murder of his mother, Annie Heyneman, and the attempted murder of his father, Henk Heyneman, at the family’s home in Kilnavart, Ballyconnell, on January 11, 2025.

The court heard that, after consuming a bottle of vodka and a large bottle of Peroni beer, Heyneman “reacted” when his mother tried to stop him drinking before allegedly launching a savage attack with a near-30cm kitchen knife.

At Courtroom 20 of the Criminal Courts of Justice in Dublin, prosecution counsel Gerardine Small SC, instructed by Monica Lawlor BL and Gerry Keane BL, outlined the events as Detective Inspector Adrian Durcan of Monaghan Garda Station gave evidence.

Heyneman, one of five siblings and a former accounting technician student who had also lived in the UK, sat silently in the dock wearing a black hooded top, his head bowed for much of the hearing.

The court was told that, for almost a decade, Heyneman had struggled with self-harm, psychiatric referrals and increasingly disturbing paranoid beliefs. His family grew alarmed as he became convinced phones and laptops were being hacked and bugged. He reportedly wrapped electronic devices in tinfoil, and hated hearing his name spoken near them. He even asked to be removed from the family WhatsApp group as his delusions escalated in early 2024.

Family messages read in court described him as “always drinking”, while relatives had discussed asking him to leave the family home. Annie Heyneman, however, feared what might happen if they forced him out.

On the evening of January 11, Annie and Henk Heyneman returned home after dining out in Cavan to find their son intoxicated. Henk went to bed shortly after 9pm but was soon disturbed by “strange noises” from the kitchen- before hearing a “scream”.

When he entered the room, he found his wife lying on the floor.

As he rushed towards her asking “honey, are you okay?”, his son turned the knife on him.

Henk Heyneman later described his son’s eyes as “massive” as he was stabbed repeatedly. He managed to retreat to a bedroom and lock the door but, when he emerged again to check on his wife, he was attacked a second time.

In a desperate fight for survival, he defended himself with a clothes horse before escaping through a side door despite catastrophic injuries.

Shortly after 9:15pm, a blood-soaked Henk Heyneman staggered to the nearby home of neighbours. The neighbour told the gardaí that one of his ears was “hanging off” and blood was “pooling everywhere” from stab wounds to his chest and arm.

He reportedly told neighbours his son had “gone crazy” and begged them to call gardaí and an ambulance while warning them not to go near the house.

Armed Support Unit members arrived shortly after 10pm to find smoke billowing from the open front door and the fire alarm blaring inside.

Gardaí discovered large amounts of blood in the hallway before deploying a flashbang device and entering the smoke-filled home in “difficult conditions”.

In the kitchen, partially hidden beneath a coffee table, officers found Annie Heyneman lying face down with multiple stab wounds to her upper chest.

She was conscious, but despite frantic first aid efforts by gardaí and paramedics, the 55-year-old mother was pronounced dead at 11:08pm.

The fire brigade later discovered the remains of a laptop and other electronic devices burned to ashes near the stove.

The court heard Heyneman fled the scene, driving in the family car around 6.7km to Ballyconnell before abandoning his car and entering the Big Bites takeaway. Gardaí received a 999 call at 9:43pm and arrested him around 10:30pm.

When arrested, he had blood on his hands and allegedly told officers he did not know what had happened. He also claimed he had been sexually assaulted as a child and said an argument with his parents had escalated before “the next thing I remember was the house was upside down”.

The owner of the takeaway described Heyneman as looking frightened, and appeared nervous.

During interviews, he claimed he could only remember events “in flashes” and admitted drinking heavily between 5:30pm and 6pm.

Asked whether he could have helped his mother, he reportedly replied chillingly: “I should have taken her with me.”

Medical evidence revealed the ferocity of the attack.

Professor Linda Mulligan, Chief State Pathologist, told the court Annie Heyneman suffered at least 14 stab wounds to the trunk, upper body and neck.

One of the most devastating injuries severed the left jugular vein, causing catastrophic blood loss. The deepest wound penetrated 20cm, while another measured 3.9cm in length.

She died from hypovolemic shock caused by extensive blood loss due to multiple stab wounds.

Henk Heyneman suffered 26 separate stab wounds to the scalp, neck, chest and abdomen, as well as a complex fracture to the left orbital wall.

Doctors activated a trauma team when he arrived at Cavan General Hospital at 11:18pm before he was later transferred to the Mater Hospital trauma centre in Dublin because of the severity of his injuries.

The court heard he continues to suffer ongoing problems with his left eye, has already undergone surgery and requires further corrective procedures. He now struggles with social anxiety, difficulty sleeping and will require psychotherapy.

Photographs of the bloodstained scene, Mr Heyneman’s injuries and the damaged family home were handed to Justice Tony Hunt, who remarked they were “not very nice”. Images shown in court included the knife used in the attack, its tip bent inward from the violence inflicted.

The defence heard that Heyneman had no previous convictions and had cooperated fully with gardaí. The court was also told he had previously been hospitalised for depression in 2014 and 2015 and, in 2023, was admitted to Cavan General Hospital after claiming a girlfriend had suffered a miscarriage- though investigators later found no evidence the woman existed.

Evidence was also heard that after the killings, Heyneman started a fire using tissues before burning electronic devices, later telling gardaí “everything was going wrong”.

Psychological experts assessed whether he was suffering from a psychiatric disorder at the time of the killing, but concluded he had significant mental health concerns.

Four victim impact statements were then read before the court.

Henk Heyneman described life since the killing as “a living nightmare”.

He said every corner of the family home reminded him of his wife of 33 years — a devoted mother who loved baking homemade cakes, spending time with family and working as a community health worker.

“I am left alone now. We should have grown old together,” he said.

He added that her death had left “a void that can’t be filled”.

He also spoke movingly about the emotional impact of losing personal devices and online accounts in the fire, saying rebuilding passwords and accounts felt like “another part of her existence being chipped away”.

In a joint statement, the couple’s children described Annie as the heart of the family and said every future milestone would now be overshadowed by grief.

They recalled how she had planned trips to Galway and Australia and had been preparing to start singing lessons.

Her daughter revealed she returned to a shop to buy the exact same outfit her mother wore on the day she died because the original clothes had been destroyed in the fire.

The family also condemned the intense media intrusion following the killing, saying they were a private family whose grief had been thrust into public view.

“We are not the same people we once were,” the children said.

They also criticised their brother for waiting 15 months before pleading guilty.

Annie Heyneman’s sister, who travelled from Australia, told the court she could not comprehend how someone Annie loved so deeply could have carried out such a brutal attack.

A family friend, who grew up in the same house and Ms Heyneman, Maureen Maguire, described Annie as a “sister” and said her death had cast “a shadow” across her “past, present and sense of the future”.

Defence counsel Keith Spencer BL later read an apology letter from Danny Heyneman.

In it, he said he had not spent “a single day” in the previous 16 months without thinking about the pain he had caused.

He acknowledged he had been raised in a loving and supportive home and that his parents had tried to help him.

“Sorry, I’m sorry,” the letter concluded.

The court heard updated psychiatric reports completed in March 2026 again ruled out any major psychiatric disorder at the time of the killing.

Judge Tony Hunt said every aspect of the case, including Heyneman’s mental health history, would have to be carefully considered.

The court heard Heyneman’s difficulties worsened due to alcohol and polysubstance abuse and that he developed paranoid delusions surrounding electronic devices, at times storing them in lead-lined containers.

He is currently on enhanced status in prison, where he has completed educational programmes, first aid training and emergency response courses and now works as a cleaner on his prison wing.

Defence counsel argued the offences were underpinned by severe psychological impairment and insisted Heyneman was deeply remorseful.

Sentencing was adjourned until June 2 at 10:30am.