The tot was fed the culinary crime at Doncaster Royal Infirmary during a recent one-day stayover for breathing difficulties.
After the Doncaster Free Press shared photos of the meal with health chiefs, both they and the catering firm who provides patient meals at the Thorne Road site apologised.
A relative of the youngster who preferred to remain anonymous said she couldn’t believe the boy been served it.
They said: “It was awful, absolutely disgusting. It had green mould on it and it smelled horrible as well. Other people had pizza and theirs was nothing like that at all.
“We had to go out and get him something else. There was no way on earth we were feeding him that.”
The meals at Doncaster Royal Infirmary are ‘contracted out’ to caterer Sodexo.
A spokesperson said: “We take food quality and safety extremely seriously. All our children's meals are freshly cooked at the time of order and we apologise that the presentation is not at the standard it should be.
“We encourage feedback from patients, their families or staff at the point of service so we can continually monitor and drive improvements to the service we provide.
“Please be assured that we have shared the images with the team and will be undertaking some coaching and refresher training with them.”
Kirsty Edmondson-Jones, director of estates and facilities at Doncaster and Bassetlaw Teaching Hospitals, said: “We work very closely with our catering partners Sodexo and our patients to ensure that our food not only meets all quality standards, but is also appetising for our patients and we are sorry that on this occasion we did not meet these standards..
“We will continue to outline our expectations with our catering team, to ensure our patients receive, and are served, the very best.
“We apologise to the family for this inconvenience and we would be pleased to follow up on their concerns if they get in touch with our patient advice and liaison service on 01302 642764.”