Ian Ramage, consultant nephrologist at Yorkhill Children’s Hospital in Glasgow, has treated Bo since he first arrived from Aberdeenshire in May 2012.
Mr Ramage said: “I think the darkest days were not the times when he was most unwell, but when we realised that he would pull through and that he would be blind and require a stoma.
“All our energies had gone into keeping him alive, then we realised the burden his health would have on him and on Lucy.”
He said most children make a full recovery from E. coli, but added that those who do not generally suffer renal failure – as Bo did – and require a kidney transplant
However, the state of Bo’s bowel, which was left with five holes in it after being attacked by the bacteria, further complicated his case.