The distraught parents of Claire Roberts, one of the children at the centre of the hyponatraemia inquiry, say they hope the fresh inquest ordered by the attorney general will finally uncover the truth about her death.
The nine-year -old died at the Royal Hospital for Sick Children in 1996.
Speaking as the inquest opened in Belfast, Claire’s mother Jennifer described how her only daughter’s death has destroyed their lives.
A medical expert told the inquest Claire’s case was extremely unusual and challenging, with many children being admitted to hospital with similar symptoms who make a full recovery.
Dr Robert Scott-Jupp said it was his hypothesis that fluid mismanagement caused hyponatraemia, which in turn led to a cerebral oedema which ultimately resulted in her death.
The doctor also believes Claire showed symptoms of viral encephalitis but he accepted that diagnosis remains unproven.
In January, a public inquiry into the deaths of five children in hospitals here found four were avoidable.
It’s chairman Mr Justice O'Hara concluded that the first inquest into Claire's death was wrong.
He also said there was a cover-up into her death which was not referred to the coroner immediately to “avoid scrutiny”.
The inquest is expected to last for four days.