Toddler Mason Lee photographed in "piles of vomit" the day before he died.

An insight into the tormented final days of Queensland toddler Mason Lee has come to light, as two of the three people charged with manslaughter over the 21-month-old’s death appeared in court earlier this week.

Mason’s mother Anne-Maree Lee, step-father William O’Sullivan, and step-father’s housemate Ryan Hodson were all charged following the police’s discovery of Mason in June, with Lee and Hodson appearing in court on Monday.

During her appearance, the court heard that 27-year-old Anne-Maree received a text message and image of her son lying in “piles of vomit” the day before he died.

The message was allegedly sent to Anne-Maree from her partner, William O’Sullivan.

Mason Lee. Source: Channel 7. 

The court also court heard Anne-Maree was in an abusive relationship with O'Sullivan, who would often restrict her access to Mason and held an "undue influence" over the young boy.

Police also claimed to have obtained CCTV audio that captured Hodson verbally abusing Mason.

"Shut the f*** up or I'll hit you in the head,” the audio allegedly captures Hodson saying.

Both Lee and Hodson were denied bail, with O'Sullivan set to appear within weeks.

Mason Lee's mother appears in court. Post continues... 

Mason Lee is believed to have died from peritonitis, a condition usually the result of a fungal or bacterial infection caused by an abdominal injury or an underlying medical condition.

Detective Inspector Paul Schmidt said at the time that the trio has been accused of failing to provide care for the toddler, but it was not clear who inflicted the boy’s injuries.

Attending the hearing on Monday was Mason's aunt, Shauntel Lee, who said that while she was happy bail had been denied, ultimately, "there's no justice for Mason".