A violent thug who beat his five-year-old step-son to death over a lost shoe has jailed for life.
Iheanacho was dating Alex's mother, Lily Breha, when he took Alex to a park in Catford on November 20, 2016.
Alex had misplaced one of his trainers, which angered Iheanacho so much he battered him unconscious.
Witnesses described hearing Alex's fearful voice saying "sorry" followed by loud banging and the Iheanacho screaming about the loss of a shoe in Mountsfield Park.
Instead of rushing the boy to hospital, he carried him to a local cab office and went to Ms Breha's flat - despite being just five minutes from a hospital.
Ms Breha told the court how she wanted to call an ambulance but Iheanacho, previously convicted for violent crime including abusing ex-partners, prevented her from doing so.
She said she started screaming when she saw Alex was "unconscious and his face was disgusting".
She told the court she kept shouting at Iheanacho "What have you done?" but in return received "hardest punch I had in my life".
She then told the jury Iheanacho "tried to strangle me, pretty much his intention was to try kill me, is all I can say".
During this attack where he kneed her in the chest, jumped on her back and tried to choke her, Ms Breha noticed Alex's face turning blue and his breathing stop and grabbed the phone.
Alex was first taken to Lewisham Hospital but was found to have swelling in his brain, so he was transferred to Kings College Hospital where he died following an unsuccessful operation on November 22.
Iheanacho told paramedics several different stories about how Alex had received his injuries and also asked Ms Breha to say she was with Alex at the park as it "looked bad - Alex was in my care".
The Hounslow man did not go to hospital with the boy he had beaten but arrived later and told police he had been with Alex's mother at the park. He later changed his story.
"Alex was so small but he was my strength and my purpose for living," she said. "The hardest thing I have ever had to hear, was that my child died. I remember it like it was yesterday.
"Lying next to him in a hospital and praying that everything would be fine, that he will open his eyes.
"I didn’t even get to tell him I love him. All I got was to put my hand on his chest and feel every single one of his final heartbeats."
Detectives later discovered Alex's missing shoe in the park.
Detective Chief Inspector Tony Lynes of the Met's Homicide and Major Crime Command said: "Iheanacho subjected that poor little boy to a brutal assault after flying into an uncontrollable rage just because Alex lost one of his shoes.
"Afterwards Iheanacho came up with various stories to try to cover his tracks, insisted his girlfriend lie for him and attacked her when she tried to get medical help for her unconscious son.
"It is no surprise the jury easily saw through his stories and while nothing can bring Alex back, I hope Iheanacho's conviction today provides his mother and father, and their families with some comfort."
An NSPCC spokesperson said: “Iheanacho should have been caring for Alex, but instead he violently robbed him of the chance to live a long and happy life. It is right that he is now behind bars.
“Babies and young children are entirely dependent on those who care for them and we all have a duty to look out for their welfare.
“We urge anyone concerned about a child’s welfare to call the NSPCC Helpline on 0808 800 5000 as it could save a life.”
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