A mother and her long-term partner have been found guilty of murdering their 15-year-old son, who died after a campaign of torture at their Huddersfield home.
Sebastian Kalinowski died of an infection caused by “untreated complications of multiple rib fractures” after weeks of “cruel assaults and abuse,” prosecutors said.
Sebastian was beaten with a bed rail, whipped with an extension cord and stabbed with a needle by his mother Agnieszka Kalinowska, 35, and her partner Andrzej Latoszewski, 38, a jury heard.
The boy, who moved to Poland to live with his mother in the UK less than a year before she died in August 2021, was also forced to complete “humiliating” exercises.
Kalinowska wept loudly in the dock after being found guilty of her son’s murder.
Police had seized CCTV cameras from the home of Kalinowska and Latoszewski after they were arrested in connection with Sebastian’s death.
Prosecutors said the cameras had been installed in part to “remotely monitor and exercise control over Sebastian.”
The seized footage showed the boy being more severely attacked by Latoszewski, but his mother was “involved at various times”, jurors heard.
CCTV footage from the day of Sebastian’s death showed Latoszewski removing him from his bedroom at 8.25am before bringing him back 15 minutes later, “naked, clearly wet and unconscious” and trying to resuscitate him.
The emergency services were only called after Sebastian had been unconscious for around two and a half hours.
The boy succumbed to an infection caused by “untreated complications of multiple rib fractures.”
Kalinowska and Latoszewski denied murdering Sebastian but were found guilty at Leeds Crown Court today.
Latoszewski had admitted manslaughter on the second day of the trial, while both defendants pleaded guilty to child cruelty a day later.
Kalinowska also denied causing or allowing the death of a child.
The prosecution claimed that both acted in concert to cause fatal injuries.
The judge, Mrs Justice Lambert, said the pair will not be sentenced until October at the earliest.
An NSPCC spokesman said: “In the months before his life was brutally taken, Sebastian Kalinowski’s mother and her partner, the very people who should have nurtured him into adulthood, they subjected him to cruelty and misery.
“People will wonder how any child in our society could suffer such an appalling campaign of abuse without anyone intervening.
“This is why it is so important that no stone is left unturned in the review of the circumstances surrounding their death. We would urge anyone who is concerned for the safety of a child or young person to speak up and seek support whenever has done. a concern.”