A man has been found guilty of murdering his two-week-old son in a special care baby unit in Somerset by shattering his skull and breaking his neck while nurses worked less than 5 metres away.

Experts said the injuries that Daniel Gunter, 27, caused to Brendon Staddon were like those they would expect to see in someone who had fallen from a high building, but the attack was so swift and silent that staff did not realise what was going on.

Gunter’s former partner, Sophie Staddon, 21, was found not guilty of causing or allowing the death of her son, who was born prematurely. She was also in the unit at Yeovil hospital at the time and the prosecution alleged she must have known the threat Gunter posed.

After the killing, which took place in the early hours of 5 March last year, both parents left the unit for a cigarette as nurses and medics tried to save Brendon. As well as the skull and neck injuries, he was badly bruised from head to toe and had broken legs, broken ankles and broken wrists.

A child safeguarding practice review is examining whether further measures should have been put in place to protect Brendon from his father, who had a history of violence and was controlling of Staddon.

It will also look at the actions of social services, who knew the couple’s issues and were considering whether to remove Brendon from them out of concern for his wellbeing.

Gunter has not given any explanation for the killing but police believe a motive could have been the fear that Staddon might move to a mother and baby unit, where no accommodation would be available to him.

Speaking after the verdicts on Thursday, DCI Nadine Partridge, of Avon and Somerset police, described Gunter as selfish and criticised him for laughing and joking in the dock during the trial at Bristol crown court. She said Staddon was very vulnerable and was closely controlled by Gunter.

Partridge said that in her 22 years as a detective and child protection officer she had never seen the sort of injuries Brendon suffered. “It’s horrifying. It’s almost impossible to imagine anyone doing that to a precious two-week-old premature baby.”

She said Gunter must have twisted and pulled Brendon’s limbs and may have held him by the legs and struck him against hard objects. “You don’t want to imagine what happened to him in those last moments,” she said.

Partridge said it was hard to come to terms with the fact that the attack took place in a hospital. She said: “It’s difficult to explain how that happened. As part of the review we will look at if there were any opportunities for this to have been prevented.”

Bristol crown court was told Gunter and Staddon were homeless and living in temporary accommodation in a former pub in Yeovil when she became pregnant.

Gunter limited how much Staddon ate, smoked and socialised. He had been cautioned for the battery of a previous partner and was sometimes violent to Staddon.

Social services were concerned about the couple’s ability to raise a child and in January 2024 told them they might take the baby into care when he was born. Social services staff noted that Gunter appeared more concerned about their housing situation than the possible loss of the child.

Brendon was born at 33 weeks in February last year at Yeovil district hospital, weighing less than “a couple of bags of sugar”, the jury heard.

While being looked after at the special care baby unit, Gunter repeatedly took Brendon out of an incubator despite staff telling him not to and on one occasion was suspected of removing a nasal tube.

Staff reprimanded him several times for jiggling, poking and rubbing Brendon, and nurses twice put security officers on alert when Gunter became angry. He was seen as intimidating and unpredictable.

At 4am on 5 March, two nurses were at their station on the unit when Staddon approached them and asked that Brendon be checked as he was cold. A nurse examined him and raised the alarm.

Gunter and Staddon left at 4.40am to go outside for a cigarette. They did not return or ask how Brendon was. When police arrived, Gunter told police: “She’s my witness and I’m her witness.” As he was being led to a van, Gunter said to Staddon: “Promise me, stick together.”

The jury previously found Staddon not guilty of murder and cleared Gunter of causing or allowing the death of a child on the direction of the trial judge, Mr Justice Swift. The defendants showed no emotion as the verdicts were returned.

Brendon’s grandfather Simon Gunter said: “Brendon was born early and was so tiny, but so beautiful. He was just perfect. Despite his early arrival, he was a little fighter and proved his strength in the very short life he had.

“As a family, we were so happy and excited. We had bought clothes, toys and supplies in preparation for his arrival and we all had exciting plans for the future.

“But, we have been robbed of a life of memories of Brendon. We won’t get to see his first steps, hear his first words, take him on his first holiday and see him grow into a young boy then a man. We will never have those memories. They have been taken from us and he will never be replaced.

“I hope Daniel gets what he deserves for what he did to Brendon but, whatever the outcome, it will never bring him back.

“Today, some justice has been served, but we still have many unanswered questions.”

A spokesperson for Somerset NHS foundation trust said: “This has been an incredibly distressing criminal case about the murder of a vulnerable two-week-old baby while he was being cared for in Yeovil district hospital. Our thoughts are with his wider family. We are part of the child safeguarding practice review, along with other agencies, that will thoroughly examine the circumstances around baby Brendon’s death. It is well under way and will be published in the autumn.”

In May, the trust announced the temporary closure of the special care baby unit after the Care Quality Commission said paediatric care there required “significant improvement”.

Gunter will be sentenced at a later date.