The teenage lover of a former Army medic has been jailed for five years for killing her three-year-old son.
Cameron Rose, who was 16 at the time, swung the child by his leg and his head smashed into a wall, while the boy's mother, Sadie Henry, was out on the school run with her other son.
When paramedics arrived at Miss Henry's home in Erith, Kent, Rhys Lawrie's face was so swollen they were unable to open his eyes to shine a light into the pupils. He was also found to have suffered a broken leg.
It was the second time in a week that Rose had attacked Rhys, who suffered from epilepsy so badly it left him barely able to walk.
Just four days before the killing in January last year, he had hit the boy hard enough to cause a brain injury but the boy was discharged from hospital.
Miss Henry, 28, lied to police, paramedics and hospital staff about the attacks because she was trying to hide her relationship with her schoolboy lover.
Rose, who was attending a school for emotionally disturbed children when he began the affair, was cleared of murder but convicted of manslaughter and assault causing actual bodily harm.
Sentencing him, The Recorder of London, Judge Peter Beaumont, told him: "Rhys died a dreadful, violent death at your hands and that must not be forgotten."
The couple had met at a bonfire party but they kept their relationship quiet and although Rose spent every weekend at Miss Henry's home he told his parents he was staying with friends.
The court had heard how she continued her relationship with Rose in secret after Rhys' death despite having been told that she must not have anything to do with him.
Miss Henry broke off the affair when Rose was arrested for murder in September 2011. She was cautioned for trying to cover up the relationship.
She told the court: "I felt guilty because my three-year-old son died and the person I cared about saw him die.
"I thought he died from natural causes. I thought I should have been there."
Rose, who had previously been found guilty of arson and had been cautioned twice for damaging his home, claimed the injuries were accidental and that the boy had suffered a fit.
He grinned as he came into court and gave a thumbs-up sign to the Recorder of London. The teenager has been kept in solitary confinement at Feltham Young Offenders' Centre after other inmates learned about the killing.