The family of a baby who died following a string of NHS failings were let down in the "worst possible way", the Health Secretary has said.
Jeremy Hunt apologised to the parents of William Mead, who died In December 2014, after GPs, out-of-hours services and a 111 call handler failed to spot he had sepsis caused by an underlying chest infection and pneumonia.
William's mother Melissa welcomed the apology and said that she hoped that a report into the 12-month-old's death would have far-reaching implications across the health service.
" We welcome his (Mr Hunt's) apology because it shows recognition and acceptance that sometimes the system does fail, and it's about standing up and being accountable for that," she said.
"We are quite overwhelmed to be honest. We are just a little family from Cornwall but William is going to make an impact on the world and we are very thankful for that."
The report found opportunities were missed to save the little boy's life after his parents were repeatedly told he just had a cough.
In a statement to MPs, Mr Hunt said: "Whilst any health system will inevitably suffer some tragedies, the issues in this case have significant implications for the rest of the NHS that I'm determined we should learn from.
"I have met William's mother, Melissa, who has spoken incredibly movingly about the loss of her son.
"Quite simply we let her, her family and William down in the worst possible way through serious failings in the NHS care offered, and I would like to apologise to them on behalf of the Government and the NHS for what happened."
Mr Hunt described the four areas of "missed opportunity" by health services where "a different course of action should have been taken", which would have led to William's survival.
He said the recommendations relating to 111 should be "treated as a national and not a local issue".
Call handlers on 111 are not medically trained and follow a set series of questions to identify patients who need further help.
Mr Hunt said: "(111) advisers are trained not to deviate from their script, but the report says they need to be trained to appreciate when there is a need to probe further, how to recognise a complex call and when to call in clinical advice earlier.
"It also highlights limited sensitivity in the algorithms used by call handlers in the signs relating to sepsis."
According to the report by NHS England, Mrs Mead spoke to medics at least nine times in the 11 weeks leading up to William's death. He was seen by several GPs who failed to spot that his condition was deteriorating.
On the day before his death, Mrs Mead called 111 for advice and also spoke to an out-of-hours GP who did not have access to any of her son's medical records.
The 111 call handler failed to explore further some of Mrs Mead's comments about William's condition, including that his temperature had gone from a high 40C (104F) to a low 35C (95F) - a sign of sepsis.
But the report also blamed GPs for the baby's death, saying a "significant missed opportunity was the fact that the underlying pathology, a chest infection and the pneumonia in the last six to eight weeks or so of William's life, were not recognised and treated".
Mrs Mead, 29, from Penryn in Cornwall, is now calling for those who run the 111 NHS helpline to only allow doctors and nurses to handle calls involving young children.
Earlier, she told the Press Association of her heartbreak following her son's death.
She said: "We were due to get married the day after William died. His dad, Paul, had planned the whole thing as a surprise and had bought William a little suit.
"William was an angel, he was the most precious little boy. He was happy, he was content, he injected our life with happiness.
"When we put him to bed we used to miss him because we knew we wouldn't see him again until the morning.
"We used to go in and watch him sleeping.
"William was everything we ever dreamed of."
Mrs Mead said she was reassured by doctors on several occasions that William would be OK, despite his daily vomiting, and told "every child gets a cough".
She added: "In December, he really became less playful.
"The GP failed to do a thorough examination in the last few days of his life. We were told 'It's just a cough, he will feel better in a couple of days'."
An NHS England spokesman said the death was a tragedy, adding: "To help reduce the risk of any other family going through such suffering, experts from the UK Sepsis Trust, the Royal College of Paediatrics and Child Health and the NHS are already working to prevent future similar tragic events.
"We have also recognised the need for GP out-of-hours and 111 services to work seamlessly, and they are now being combined on a rolling basis across England."
The report into William's death said he may have lived if the NHS 111 call hander had realised the seriousness of his condition.
If a medic had taken the final phone call instead they probably would have realised William's "cries as a child in distress" meant he needed urgent medical attention, it said.