A twisted teenager who killed his ex-girlfriend’s baby by brutally shaking him to death told police that they were ‘boring’ during an interview.

Carl Alesbrook, who was 16 at the time, murdered four-month-old baby Elijah Shemwell in January 2022 just weeks after meeting his mother India Shemwell.

Elijah died three days after he was found limp, pale and drowsy at his mother’s messy flat in Belper, Derbyshire.

Following his arrest Alesbrook spun a web of lies claiming he had messaged police to ask where they were when Elijah fell ill.

But a detective called his bluff in an interview saying: ‘This was a lie, there is no message saying “where are you?”

‘We have interrogated your phone and that is not confirmed on there. What do you have to say about this?’ Responding, Alebrook replies: ‘F*** all’.

The detective then quizzes him about his initial claim that he was asleep and unaware Shemwell had gone to the shops before making a sudden u-turn.

When asked about this drastic change in his story, Alesbrook rests his head on the wall and tells police: ‘I say you’re boring, man’.

Alesbrook, from Matlock in Derbyshire, denied causing any harm to Elijah but was unanimously convicted of both murder and causing grievous bodily harm with intent by the jury at Derby Crown Court on July 11.

An autopsy found  Alesbrook shook his then-partner’s son so violently he suffered ‘catastrophic’ brain injuries and broken bones.

Elijah’s mother Shemwell, who is now 23, was sentenced to three years behind bars after admitting two counts of child cruelty.

This included the fact she did not dial emergency services more quickly after Elijah became unwell.

Alesbrook admitting to leaving the baby unsupervised and taking drugs before he was meant to look after the tiny tot.

He was often left with Elijah while the baby’s mother was at work.

Medical evidence presented at the trial showed Elijah suffered brain damage from being shaken on at least three separate occasions.

He also had 17 bruises around his chest, back and stomach consistent with grip marks and suffered rib and limb fractures, while his fatal head injuries were described in court as ‘catastrophic’.

The court heard Shemwell sent a video of Elijah unresponsive with a floppy arm to friends on Facebook to ask for advice on his condition on January 1.

The jury also saw CCTV of Shemwell visiting a shop and buying milk and Coca-Cola on the night of the fatal assault.

Jurors were told Shemwell also filmed Elijah struggling to breathe before she dialled 999 at 10.33pm on January 2, leading to him being taken by paramedics to Queen’s Medical Centre in Nottingham.

He died three days later on January 5.

The court heard Shemwell had separated from Elijah’s father but ‘remained emotionally and sexually involved’ with him, which may have caused Alesbrook some frustration.

The prosecution alleged that a toothache suffered by Alesbrook at the time may also have caused him to lose his temper with Elijah.

Alesbrook denied that his tooth pain caused him to lash out at the baby and denied feeling jealous towards Shemwell’s ex-partner.

Shemwell was described during Alesbrook’s trial as ‘a thoroughly inadequate mother’ who both generally and specifically neglected Elijah and failed to seek prompt medical attention for him on both January 1 and 2.

Prosecutor Vanessa Marshall KC said Shemwell ‘failed to prioritise the needs of Elijah over her own’ and should have known Elijah was ‘testing Mr Alesbrook’s patience’.

She said: ‘It is the prosecution’s case that she should have appreciated shortly after he had been shaken, for probably the second time, that Elijah was very unwell and needed medical attention.

‘That is particularly the case when she would have seen, as we have, fresh bruising on Elijah’s face.’

Shemwell’s defence lawyer Darron Whitehead said: ‘She knows she has let down her son, she knows she has let herself down, and she has let down her family.

‘It is her inactivity, it’s her failings, that will haunt her for the rest of her life. She misses Elijah and no matter what is said in this room, or in writing, she loved her son.’

A victim impact statement by Shemwell’s mother, Rachel Shemwell, read to the court by Ms Marshall, said her daughter was ‘not the best of mums’ and things could have ‘turned out differently’ if she had asked for help.

She wrote: ‘We will never get Elijah back and can only remember the happiness he brought us in his short life.’

Mr Justice Jeremy Baker said: ‘The effect of Eli’s death on those who loved him is evident. Nothing this court can do will assuage their overwhelming sense of loss.’

The judge told Alesbrook: ‘There is only one sentence that can be imposed and that is detention at His Majesty’s Pleasure.’

Detective Chief Inspector Greg McGill, who led the investigation into Elijah’s death, said: ‘While a child himself, even a teenager knows the fatal risks posed by shaking a four-month-old baby boy.

‘The force used to squeeze his tiny body broke his ribs – while the shaking caused such significant damage that his brain became starved of oxygen leading to his death.

While India was quite simply an appalling mother, she could never have foreseen the brutal actions of Alesbrook.

‘However, it is quite clear that she could and should have taken far better care of Elijah and she will have to live with the consequences of both her action and inaction for the rest of her life.’

Shemwell, who is now 23, was described during her ex-partner’s trial as ‘a thoroughly inadequate mother’ who both generally and specifically neglected Elijah and failed to seek prompt medical attention for him on both January 1 and 2, 2022.

Alesbrook’s violent outbursts caused little Elijah bleeding on the brain, whiplash-type injuries and multiple bone fractures between November 2021 and January 2022.

He said defenceless Elijah Shemwell was ‘being a little c***’ and complained that the baby kept spitting his dummy out.

Once 999 was eventually called on January 2, Elijah was taken by paramedics to hospital where he died three days later on January 5.