Tracy Scotton's son William, who's now four, is blind, has cerebral palsy, suffers from epilepsy and will never be able to walk as a result of the trauma he suffered during his difficult birth. William requires round-the-clock care.
His mother brought a claim against Maidstone and Tunbridge Wells NHS Trust - which runs Maidstone Hospital where William was born in 2007 - alleging his injuries were caused by failures in her care before and during his birth.
At the High Court, Mrs Scotton said it had been 'hell' and "I am relieved it is finally over."
A judge found that, despite a series of scans showing William's unusually large size of 8lbs at 34 weeks, not enough was done to avoid the tragedy.
Mrs Scotton, from Maidstone, Kent, was admitted to Maidstone hospital when labour started at 42 weeks - two weeks past her due date. When William was born by emergency Caesarean he weighed 11lbs 10oz.
Augustus Ullstein,QC, told the High Court in London that had midwives referred Mrs Scotton to a consultant after her 34-week scan, further scanning at 38 weeks would have led to a planned Caesarean.
According to the QC, had this happened William would have been born completely healthy.
Further blunders saw the baby left unmonitored, starved of oxygen and his heart beat lost on a monitor.
Mr Ullstein said it was all avoidable and a "sorry saga of careless mistake upon mistake".
Mrs Scotton said: "When I asked about an elective Caesarean because of William's size even when I was 34 weeks pregnant, I was told not to be silly and that the Trust didn't do them.
That's when this all went wrong. I now know I should have been referred on to a consultant. That, the hospital have now admitted, would have led to me having a Caesarean and William would now be a normal, happy and healthy four year old.
She added: "On the day I went into labour and was admitted to Maidstone Hospital I was put on constant monitoring. This meant that a midwife or a doctor had to be with me all of the time. The doctor was junior and inexperienced and the consultant was not in the hospital, but only on call, which meant that she was at the end of the telephone and completely reliant on what she was told as to my condition by the junior doctor.
"There had been no progress in my labour for some hours and the midwife was growing concerned. The doctor dismissed these concerns, ignored a number of what the internal hospital inquiry called 'red flags' and ignored the suggestions of a very experienced midwife as well that something should be done.
"The doctor's plan was to do nothing and because she told the consultant over the telephone that there were no problems, the consultant agreed with this."
Her son's lawyer Mike Williams said the hospital's internal enquiry acknowledged serious failings and accepted a number of 'red flags' had been missed.
Admitting full liability for the events which led to William's injuries, the Trust agreed to pay a lump sum of £2.6 million, followed by annual payments of between £89,000 and £212,500, to cover the costs of his care for the rest of his life.
The trust has also agreed to pay up to £600,000 fees for specialist education for William, in the event it cannot be provided by Kent County Council.
Speaking outside court, William's solicitor Michael Turner, said the settlement could result in the trust paying out around £10 million over William's lifetime.
He added: "Tracy is just the most incredible mother - she has devoted her life to William."
A spokesman for Maidstone Hospital said: "We wish to repeat sincere apologies to William and his family for the injuries which he suffered arising out of his delivery in 2007.
"The Trust is pleased that an appropriate level of compensation has been agreed between the parties to offer security for William.
"The Trust wishes to pay tribute to the dedicated care given to William by his family over the past four and a half years and wishes William and his family well for the future."
During the brief hearing, the trust's barrister, Neil Block QC, also paid tribute to William's family for the care they have given him.
He said: "I take this opportunity to apologise on behalf of the NHS for the mistakes that were made, which led to him sustaining such grievous injury.
"Unfortunately, nothing other than compensation can be provided now by the NHS. We hope that William's family now at least have one burden lifted from their shoulders, in that the financial security to provide for him in the future is now there.
May I, on behalf of the NHS, say that the loving and devoted care William has received from his parents shines out and the court can have confidence this will continue into the future.
Approving the settlement, Mr Justice Tugendhat added: "I would like to add my own personal sympathy to William's parents and pay tribute to the care which the family has devoted to William. Send him my best wishes."