A mum's innocent stunt at her daughter's first birthday party ended in disaster after she tragically died.

Faith Waterman Batistich decided to take part in a time-honoured birthday stunt to celebrate the birthday of her young daughter along other party guests by breathing in helium to raise her voice's pitch. The 20-year-old from Te Puke, New Zealand, was pronounced dead just an hour after breathing in the gas, despite her desperate family members' attempts to revive her.