The mother of a baby who died after she followed medical advice from an NHS helpline has called a report into the service's failings "soul-destroying".
The report, seen by the Daily Mail, is in response to the case of Melissa Mead's son, William Mead, who died from sepsis as a result of a chest infection in December 2014.
It concluded the non-emergency NHS helpline is "unsafe for seriously ill children" and William "could have been saved if a 111 call handler had realised the seriousness of his illness".
Mead, 29, from Penryn in Cornwall, said her son was seen by medics multiple times in the months leading up to his death and they missed opportunities to look for signs of sepsis and give William potentially life-saving antibiotics.
The "root cause analysis report" found 16 mistakes contributed to his death, the Mail said.
Multiple GPs missed the chest infection that contributed to his death.
The report said doctors were under "constant pressure" not to prescribe antibiotics, even when they believed children needed them, and they were also loath to refer people to A&E units unless "absolutely necessary" because of pressures of patient numbers.
The report concluded that a "deteriorating paediatric patient" like William was "not easily identified through the structured questioning", called NHS Pathways, used by the 111 call handlers.
The 111 call by his mother, Melissa Mead, was poorly dealt with by an adviser who would have had no more than a few weeks' training, the Mail said, and who failed to notice the "abnormal behaviour" his mother described.
Most importantly, the report found that even if used properly, the 111 system was "not sensitive enough" to pick up William's illness, a "root cause" in his death.
The report concluded that the tick-box system "lacks sensitivity to the deteriorating paediatric patient".
Mead told the Mail: "For us there are no words that can explain the profound loss that we live with after losing William. For us it is a debilitating life sentence that we re-live every day."
"There were multiple occasions in the lead-up to William's death where there were missed opportunities to treat William.
"We hope those involved in William's treatment will never make the same mistakes again. We also hope the recommendations made improve systems to ensure other lives are not lost."
Apologising to William's parents, Lindsay Scott, director of nursing with NHS England in the South West, said, according to PA: "Everyone involved in this report is determined to make sure lessons are learnt from William's death, so other families don't have to go through the same trauma.
"We're particularly grateful to Mr and Mrs Mead for their input and attention to detail, because their experiences during repeated contact with the NHS are critical to our understanding of what went wrong.
"In William's case, it's clear in looking back that opportunities to intervene more decisively were missed, but we will only be able to make a real difference if professionals across the country understand how different choices at critical moments might avert a similar tragedy.
"This report isn't about blame, but about learning and awareness. That applies not just to health staff but to parents as well, because both might be in a position where timely action is crucial."