Tyrell Cobb's mother's ex-partner Matthew Ian Scown has been sentenced to four years in prison for the 2009 manslaughter on the Gold Coast of the four-year-old boy, who died from a trauma injury to his abdomen.
Scown pleaded guilty to manslaughter in the Supreme Court in Brisbane.
He is the former de facto partner of Tyrell's mother, Heidi Strbak, who is also charged with manslaughter.
Scown is expected to be released today, after his sentence was suspended due to having already spent two years and eight months in custody.
Tyrell was found unconscious inside an apartment at Biggera Waters and later died in hospital.
Prosecutor Phil McCarthy told the court Scown called triple-0 when Tyrell began vomiting after he was put to sleep by his mother and told the operator "it looks like he's going to die".
Justice Martin Burns told the court it is not suggested Scown knew about or inflicted the fatal blow on the little boy.
In sentencing Scown, Justice Martin Burns said Tyrell would have been "in extreme pain" and "very, very ill".
Justice Burns said he acknowledged that Scown had asked Strbak to seek medical attention for Tyrell the day he died.