A teenage girl saved her mother's life by spotting the symptoms of a stroke – having learned what to look out for just two days previously in a school science lesson.
Katie Murphy, a 14-year-old from Waukesha in the US state of Wisconsin, called an ambulance after she noticed her mother Christa Murphy's speech had become muddled.
The student remembered her science teacher had told a story to help them recognise symptoms of a serious and potentially deadly brain attack.
"Her speech was all mixed up, [it didn't] make sense at all. Then I had gone back to that story, and was like: 'Maybe she's having a stroke'," Katie told local news channel WISN.
Katie said the lesson at St John's Lutheran School had made her think it was "kind of cool and weird" that difficulty speaking could be the first signs of a stroke.
Ms Murphy, 45, told the broadcaster she couldn't believe she might be having a stroke – where the blood supply to part of the brain is cut off, or when a blood vessel supplying the brain bursts – at her age.
She said she asked Katie for help after she found she was having trouble with her daily routine, including everyday tasks such as putting toothpaste on her toothbrush.
Around 85 per cent of strokes are ischaemic, which means they are caused by a blockage or blood clot in an artery or vessel that supplies the brain with oxygen.
Someone in the world has a stroke every two seconds and they occurred 152,000 times in the UK in 2016, according to the Stroke Association.
"I tell stories constantly, I knew a story was something they would grasp onto," said Katie's teacher Beth Tomlin.
Other symptoms of stroke include sudden numbness or weakness, especially on one side of the body and in the face, arm or leg; trouble seeing in one or both eyes; and sudden confusion, dizziness or lack of coordination.
