Heartbreaking footage shows a toddler moments before being beaten to death by his mum's boyfriend.
Police uncovered the video of three-year-old Kemarni Watson Darby holding hands with his mum Alicia Watson as they strolled home.
Hours later, Watson’s boyfriend Nathaniel Pope beat Kemarni so badly that he was unable to walk, reports Birmingham Live.
DI James Mahon, who led the investigation, described the clip as one of the most haunting he has ever seen.
"I think the thing that sticks with me the most, and it haunts me really, is watching Kemarni take those last steps up the stairway to the flat.
"He's with Watson, who should have been there to care and protect him.
"And he was going into his home, which should have been his safe place, his haven, and ultimately, as you watch that footage, he's walking to his death. I think that footage will stay with me forever."
Pope was jailed for life following the horrifying murder in the Black Country, West Midlands.
Watson was sentenced to 11 years in prison for her part in her son's death.
Police believe Pope began beating Kemarni two months before he died in West Bromwich in June 2018.
The murder trial heard evidence of how the "boisterous" toddler was seen to have behavioural issues at nursery and could barely string sentences together.
DI Mahon said: "That was obviously a result of that abuse. He’d started to lose his ability to have emotions at either end of the scale of experiencing happiness or sadness.
It’s terrible to think what life he was living in there."
Pope used snapped electrical cables to force the door shut and lock Kemarni in a room at the family’s two-bedroom home in Stanton House.
The West Midlands Police officer added: "How anyone could deliver a fatal blow to a three-year-child on the pretence that he is naughty is absolutely shocking.
"The cable was used to lock him in the bedroom when he was described as being naughty. That’s just abuse, a child shouldn’t be locked away.
"Watson did use physical violence to chastise the children. Whether that gave him the green light because he is a violent individual, we don’t know.
"He’s never shown any remorse or accepted any responsibility."
Watson knew about Pope's abuse of her son and even stayed in a relationship with him after her son was killed.
But at trial, she blamed her ex-boyfriend for her son's murder and branded Pope a 'cold-hearted liar' after he denied he ever hurt the child.
DI Mahon said: "There are other elements that shock you too, it’s the fact that Watson, his mother, stood by Pope knowing what he had done afterwards.
"I can’t fathom why anyone would ever do that, and at the stage she is either trying to do that to absolve herself from the ongoing abuse or to protect him.
"Not only did she know what was happening but she was involved in what was happening.
"The court heard evidence of her physically assaulting Kemarni so I think her behaviour and her abuse of Kemarni probably allowed Pope to commit the most serious violence later on."
The detective insisted there were no missed opportunities by the force as no concerns about Kemarni’s welfare were raised with West Midlands Police or Sandwell Council.
Historic injuries 'would not have been causing him pain' when Watson took him to a medical centre hours before he died. the detective added.
Bruising and scratches noticed by nursery staff and loved ones were also 'explained away' by Watson as being 'usual bumps'.
Watson and Pope were arrested on the day Kemarni died on suspicion of child cruelty.
They were released under investigation and interviewed again about two months later before being arrested on suspicion of murder in June 2018.
A trial at Birmingham Crown Court stretched over six months and saw jurors presented with evidence over 10 weeks. They returned their verdicts on April 12, with the criminals sentenced today.
DI Mahon said it took more than three years to bring the case to trial due to delays 'out of the control' of police and the Crown Prosecution Service.
He said: "The process of ageing bone fractures can take up to 12 months so that had to be done before we got the final pathology report and then we’d have to have paediatric experts to understand exactly how the injuries were caused.
