Medics in Northern Ireland should be legally forced to come clean about errors in their care, a public inquiry said.
The mother of one girl who died from avoidable negligence by doctors said any new duty of candour should be called Raychel's Law in memory of her daughter.
Inquiry chairman Sir John O'Hara QC investigated the deaths of five children and heavily criticised a "cover-up" by some consultants, accusing some doctors of behaving "inadequately, evasively, dishonestly and ineptly".
The High Court judge found three deaths from hyponatraemia, a lack of sodium in the blood, were avoidable and the youngsters received unacceptable care during the administration of intravenous fluids.
He criticised a failure to learn lessons and a circling of the wagons by some medical professionals.
He added: "It is time that the medical profession and health service managers stopped putting their own reputations and interests first and put the public interest first."
Raychel Ferguson, nine, died in 2001 at the Royal Children's Hospital in Belfast shortly after transfer from Altnagelvin Hospital in Londonderry.
Her death resulted from hyponatraemia brought on by fluid therapy which had not properly replaced her sodium levels.
Her mother Marie Ferguson said: "What I have experienced during this journey is inexcusable. The trust and their lawyers abused their position by trying to cover up the truth."
She added: "No family should have to go through the mental and physical stress, hurt and undermining that we are still going through.
"I would like in memory of Raychel the introduction of a statutory duty of candour - Raychel's Law."
Sir John said the service has to improve so that mistakes were faced up to and families were told what went wrong and what will be improved.
"That is why in chapter nine, in my first and primary recommendation, is that as a matter of urgency a statutory duty of candour should be introduced.
"That would impose a duty to tell patients and their families about major failures in care and to give a full and honest explanation."
He said health service representatives knew much more than they were prepared to share with the Fergusons and tried to mislead a coroner.
He added: "How much anguish, anger and frustration would the Fergusons and other families have been spared over the years if they had just been told the truth from the start?"
Adam Strain, four, died at the Royal in 1995 from hyponatraemia having undergone renal surgery.
Sir John said an anaesthetist supposed to be monitoring his fluids maintained a "baseless" justification of his actions for many years.
The inquiry chairman added: "My belief is that evidence was withheld about what happened there, and that is truly shocking."
The parents of Claire Roberts, nine, were "deliberately misled" and consultants covered up after her death, the chairman said.
The inquiry also examined events following the death of 17-month-old Lucy Crawford in April 2000 and issues arising from the treatment of 15-year-old Conor Mitchell in May 2003.
Dr Cathy Jack, medical director of Belfast Health and Social Care Trust, said she was saddened by the findings.
"There were elements and statements in that report that made me feel ashamed on a personal level."