They had believed his death was solely caused by a lack of oxygen caused at some stage during the pregnancy until collecting their son's records in 2015. They were gobsmacked.
"We weren't aware of other issues to do with the fact it wasn't referred to the coroner, we didn't know that the Resuscitaire wasn't working or user error, we didn't know about the lack of training of staff and we didn't know their [protocol] for multiple birth was out of date," the mother said. A review into his care was only completed in 2015 after they complained.
The family now believes they could have had a different outcome if the obstetrician had acted sooner.
The woman was 35 weeks pregnant when she went into labour with her first borns. She was taken to the birthing unit at the DHB and assigned the on-call obstetrician as hers was overseas.
She laboured for 12 hours until her daughter was born with the aid of forceps. The second baby's head was still high so the obstetrician administered the drug Syntocin to increase contractions.
During that time the baby's heart rate fluctuated, dropping as low as 66 beats per minute then rising to 144bpm.
The baby boy was finally delivered 38 minutes after his sister with the umbilical cord around his neck and he was not breathing.
In the HDC report, specialist obstetrician and gynaecologist Dr John Short said he had "serious concerns" about the monitoring of the baby's heart rate and the lack of action between the birth of the two babies "when his heart rate deteriorated considerably and the trace becomes grossly abnormal".
He said the baby's heart rate was "so frankly non-reassuring" that urgent assisted delivery should have been carried out immediately after the first baby was born.
The mother, who has since had another child, hoped the DHB would learn from the findings so no one else would have to go through what she described as the worst time of their lives. "The purpose of us going through this was to make change - our friends and our family have their babies at that hospital and we wanted to make sure things were changed and made right.
"We weren't out on a witch hunt to make somebody accountable, but we wanted these failings recognised and dealt with and if we could at lease educate other people that if they feel like something is not going right to say something."
She wanted the DHB to make sure protocols were up to date, that staff were not out of their depth and erred on the side of caution, and reviewed their staffing levels.
"I hope they do now follow up events like this properly and I believe they've had some training about referring things to the coroner. I just really wanted the DHB to have a bit of a shake-up so it doesn't happen to someone else."
In the Health and DIsability Commissioner's report, the health board acknowledged there were issues and said steps had been taken to resolve them.
It had reviewed its delivery guide for twins, developed an umbilical cord blood gas protocol, the purchase of a second resuscitaire unit and ongoing training in relation to newborn resuscitation, newborn life support traching and plans to transition to an electronic coronial referral system.
The parents have been constantly reminded of their son's death from the early days when they had to explain to people why there was only one baby to now when they are answering his surviving twin's questions about her brother.
"You can't not relive it, and you can't not deal with the what ifs. It's very difficult because we see our other daughter and we know how he possibly would have turned out."
