Welfare officers visited Mason Lee's mother, minutes from where he lay dying at stepfather's home

Child safety officers visited Mason Lee’s mother three days before his death, failing to discover he was dying at another home, only a kilometre away, court documents allege.

It’s alleged Anne Maree Lee told welfare officers that Mason was not home, and was staying with his stepfather William O’Sullivan at Caboolture South, only four minutes drive from her home.

She believed the child protection officers would try to see the toddler there, however he died in pain on June 11, suffering from a ruptured intestine.

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Sickening photo sent to Mason Lee's mother

Mason, who was 21-months-old at the time, had suffered five days of vomiting and allegedly had his faced rubbed in it “like a dog,” the Courier Mail reports.

Lee, O’Sullivan and 17-year-old Ryan Hodson, who also lived at the home where Mason died, have been charged with manslaughter over the toddler’s death.

It’s alleged the trio failed to provide adequate medical treatment for Mason.

Last week in court, Hodson’s girlfriend Sheila Low alleged child protection officers arrived at Lee’s home on Compass St on the Tuesday or Wednesday before Mason’s death.

“She (Lee) told me that Child Safety was assisting her and did a welfare check at her house three days prior,” Ms Low, 30, told police.

“I asked about Mason and she said that they hadn’t seen him as he was with Will (O’Sullivan). She was told that Child Safety were going to try to see Mason at Will’s.”

Court documents reveal medical experts believe the toddler died at O’Sullivan’s Deanne Court home from a perforated intestine.

It’s believed the injury was caused by “a punch or similar” to Mason’s upper abdomen, up to five days before the toddler’s death.

Doctors told police medical intervention could have saved Mason’s life.

The toddler raised eyebrows of medical staff in February, when he was admitted to Brisbane’s Lady Cilento Children’s Hospital.

It was then doctor’s suspected he had been abused.

Ms Low claimed she had raised concerns with Hodson about O’Sullivan, who allegedly showered with Mason for “more than an hour at a time”.

She told police Hodson replied that he wasn’t going to “accuse my mate”.

Hodson had also told Ms Low how he encouraged O’Sullivan to rub the toddler’s face in vomit.

“F*** him. The stupid dog c***. I told him ‘you want to act like a dog, get on the floor like a dog’,” Hodson allegedly said in a recording.

Ms Low told police she had previously questioned O’Sullivan’s treatment of Mason.

She claimed she saw Mason two days before his death, lying on O’Sullivan’s bed covered in vomit.

Police claim O’Sullivan left the toddler alone for about 20 minutes on the night of June 10.

He was seen on CCTV outside his front door telling himself “I can’t f***ing do this”.

O’Sullivan left the property and eventually returned with another man, Shane Gruber – who called emergency services.

Last week Hodson was granted bail, set to reappear in court next month.

O’Sullivan, 35, and Lee, 27, remain behind bars and are due to face Caboolture Magistrates Court on Tuesday.

The Department of Communities, Child Safety and Disability Services told the Courier Mail they were unable to comment on the case as it was before the courts.