The initial presentation of pediatric diabetes is variable, making prompt diagnosis and treatment challenging. The overlap between type 1 and type 2 diabetes and presence of developmental delays can complicate diagnosis, resulting in delays and severe illness at presentation. Here we describe a case of a 13-year-old male with autism and attention deficit hyperactivity disorder who presented with severe diabetic ketoacidosis, multiple organ failure, and shock. Within 2 weeks of this initial presentation, he had further clinical decompensation due to an intestinal perforation. Cultures from resected gastrointestinal tissue grew mucormycosis, protracting his hospital stay and recovery. He was able to go home several months later with remarkable improvement. This case highlights the necessity of careful history taking and early testing, and how investigation for rare complications of diabetes is vital when patients do not improve as expected.