A teenager from Caerwent in Monmouthshire died suddenly from an ultra-rare infection after using a tampon for the first time.
Natasha Scott-Falber died on Valentine's Day five days after falling ill with what was thought to be the norovirus.
The 14-year-old's family now believe she died from toxic shock syndrome - a bacterial infection that affects just 40 people a year in the UK.
Her family have now launched a campaign to raise awareness of the condition so other sufferers spot the signs earlier.
TOXIC SHOCK SYNDROME
The infection is caused when usually harmless Staphylococcus aureus or Streptococcus bacteria, which live on the skin, invade the bloodstream and produce dangerous toxins.
This causes a sudden high fever, a massive drop in blood pressure resulting in dizziness and confusion, and occasionally vomiting and diarrhoea.
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