In 2015, when Harry Long from Melbourne, Australia, was 16 and on holiday with his family in Malaysia, he experienced an excruciating pain beneath his shoulder blade mid-way through eating a giant bowl of Honey Stars cereal without milk.
He described the pain being "as if someone had come up from behind and stabbed me" and staggered back to his room to recover. After 20 minutes he felt fine, but experienced frequent shortness of breath over the next few days. It wasn't until a week later when the family were in Singapore that he went to a hospital and was X-rayed.
The X-ray revealed that he had inhaled one of the cereal stars and its sharp point had punctured his lung, causing it to collapse. That had caused the initial agony, which had subsided once the lung had totally collapsed, leaving him breathing with one lung for the rest of the week.
Doctors told him he was extremely lucky to have survived the flight to Singapore - had the plane hit a certain altitude the change of pressure could have killed him.
theguardian.com, 6th May 2022