"As a father, there's nothing harder than seeing your baby boy fighting so hard for his life and those people that you trusted [who] would help him in his fight didn't help him. I couldn't even get in there and help him fight it," his father David Chaloner said.
"Those people at the hospital ... they should have done those tests, he would've been alive today.
"It was real devastating."
He said he tried talking to his son to fight it out but didn't make it.
"It was my daughter's birthday - it's really sad because the day of the birthday is the day her brother died. That's going to stick forever. I'd give anything to have him back."
He said it shouldn't have happened and he wanted something done about it.
"Haven't even received an apology from the DHB ... got it from the doctors."
Mr Chaloner said he didn't receive any further details from the DHB, just the coroner's report.
Canterbury DHB chief medical officer Dr Sue Nightingale in a statement said: "On behalf of the DHB, I express my sympathy to the family of this young boy.
"As the death has been referred to the coroner, we are unable to comment further."