Queensland toddler Baden Bond was allegedly found in a urine- and faeces-covered cot before he disappeared, with the Crown saying he was killed by his own parents.
His mother Dina Colleen Bond, 43, was on Thursday denied bail in the Brisbane Supreme Court after prosecutors successfully argued she could interfere with witnesses.
The court heard Bond told a visiting relative in 2007 that Baden was "a little c***" and refused to let them see him.
Baden's father Shane Arthur Simpson, who is also charged with murder, allegedly told a witness on a separate occasion that the 22-month-old boy was "evil".
The witness also alleged they found Baden in his cot covered in urine and faeces.
Baden was last seen on March 27, 2007 during a visit from the Department of Child Safety.
Police allege he died sometime between then and May 17, 2007 at his Wagawn Street home in Woodridge, south of Brisbane,.
The court heard Baden's parents moved in the middle of the night in August 2007 to NSW without telling anyone and did not contact family members for a year.
They have allegedly continuously lied that Baden was either in foster care or staying with relatives.
They were charged in March 2017 after an extensive investigation found no record of Baden attending any school or medical centre in the past 10 years.
The court also heard Bond had another child, a three-month-old son, die in her care but that death was not suspicious.
Bond's mother Carol Bond had offered to let her daughter stay with her and keep her off drugs if she was released on bail.
But Justice Sue Brown found Bond was too great a risk of interfering with witnesses and not turning up to court.
Carol Bond attempted to kick a photographer as she left court.