The Public Prosecution Service has dropped investigations into the deaths of two children in NI hospitals.
Raychel Ferguson's death is still being investigated
It was alleged that Lucy Crawford and Adam Strain died needlessly of sodium shortage due to the incorrect administration of fluids.
The PPS is still investigating the death of Raychel Ferguson, nine, who died in similar circumstances in 2001.
But Raychel's mother, Marie, said she was disappointed there were not going to be prosecutions in the other cases.
She said she thought that decision was wrong.
"There has been three deaths and no-one has been accountable," she said.
"We were really hoping that with the police investigation that something good was going to come out of it and we were going to get some kind of justice and in my case it doesn't really leave me with much hope at the minute.
The three children's deaths have been the subject of an inquiry
"But I'm clinging onto that wee bit of hope that they come back with news that I'm hoping to get. At the minute I think it looks quite doubtful."
Raychel died four days after routine surgery to have her appendix removed at Altnagelvin Hospital in June 2001.
Adam Strain, four, from Belfast, died at the Royal Hospital for Sick Children while 17-month-old Fermanagh girl Lucy Crawford passed away at the Erne Hospital, Enniskillen in 2000.
In November 2004, the then Health Minister Angela Smith launched an inquiry into the three deaths.
The inquiry was suspended in 2005 so that the police could investigate the deaths.
But the PPS has now announced there will be no prosecutions arising from the police investigations into the deaths of Lucy and Adam but that the case of Raychel remains under consideration.
No-one from the PPS was available to comment.