Adam Johnson, 26, and Kylie Smith, 25, both of St Helens, have denied causing the death of their one-year-old son, Maero Johnson. The child died in hospital in August 2023.
At Liverpool Crown Court, the pair pleaded not guilty to causing or allowing the death of a child between 5 June and 24 August 2023. They also denied two counts of cruelty to a person under 16.
A post-mortem examination indicated Maero died of ketotic hypoglycaemia and severe malnutrition. Mr Johnson pleaded guilty to a charge of possessing cannabis.
The defendants were granted unconditional bail ahead of a pre-trial hearing on 5 April 2027. A trial, expected to last four to six weeks, is due to begin on 9 April 2027.