A 12-year-old girl, Mia-Mai Grace Williams, described as “fit, happy, and healthy,” tragically passed away after collapsing at her grandparents’ residence. Mia-Mai was found in cardiac arrest in one of the bedrooms with signs of vomiting, receiving immediate life-saving treatment. Originally from Merthyr Tydfil, Wales, she was first taken to Prince Charles Hospital and later transferred to Noah’s Ark, University Hospital of Wales, where her condition worsened, as revealed during an inquest at Pontypridd Coroner’s Court.

Despite showing no prior signs of illness, Mia-Mai fell critically ill while visiting her grandparents with her family. She sadly succumbed to her condition on August 11, 2024, with reports from Wales Online suggesting that an infection triggered the cardiac arrest that led to her untimely death. A post-mortem examination indicated that Mia-Mai had myocarditis, a heart infection believed to have caused the cardiac arrest that resulted in her passing, as outlined in the inquest’s conclusion on March 2.

Coroner Patricia Morgan from the South Wales Central area recorded Mia-Mai’s death as a natural outcome of multiple organ dysfunction, cardiac arrest, and lymphocytic myocarditis. The coroner emphasized Mia-Mai’s prior good health, stating that she showed no signs of being unwell before the tragic incident at her grandparents’ home. The inquest, which commenced on August 21, 2024, and concluded on March 2, 2026, shed light on the sequence of events leading to Mia-Mai’s unexpected demise.