Speaking to the Mirror, her mum, Sharon, 41, explains that Megan was diagnosed with the extremely rare 'Hair Brushing Syndrome' three years ago.
She recalled how she was brushing the then 10-year-old's hair when she 'flopped over and her lips turned blue.'
The shocked mum thought her young daughter was having a fit, so called paramedics.
Medics have told the family, who live in Wishaw, Lanarkshire, that they had only ever heard of ONE case Hair Brushing Syndrome before.
It is though that Megan developed the condition after suffering complications at birth - she was born weighing just 2lb 5oz and had a had a diaphragmatic hernia which pushed her stomach into her chest, preventing one of her lungs from growing.
Sharon said that despite her condition Megan is a 'very happy and lively young girl', adding: "She can't rub balloons at parties and can't wear any shiny clothing. She really did defy all odds."