"If she had not been doing so well then perhaps I would have done more."
He said the youngster was completely unresponsive during initial resuscitation attempts.
"I carried on with first-aid type things before handing the little one over to the ambulance staff, that's the best way to put it - nice and simple," he said.
"You could say I dealt with a situation to the best of my ability which is no more than anyone else would do in the same situation. There was a little boy, something was broken, and it was a matter of fixing it."
He was quick to praise the relative initially carrying out CPR on the toddler. "I believe, through a combined effort, the little boy was given the best chance anyone in that situation could be given."
However Awakeri Hot Springs campground owner Kevin Haig tells a slightly different story. "The man you are talking about did most of the CPR while his wife assisted," Mr Haig said. "I was watching over his shoulder the entire time including when he gave the little boy oxygen. It was very clear he knew what he was doing and knew it well."
Mr Haig said the situation looked pretty grim for some time. "When the youngster finally started coughing and then crying, I think I even managed a small smile. He was bundled into an ambulance and looked to be doing okay so I was quite surprised to learn he had been flown to Starship Hospital in a bad way."
The toddler was yesterday reported to be in a stable condition at Starship children's hospital. Mr Haig said he was glad to have had Mr Henwood around on Monday. "Even though I've trained in first aid, having someone there to give the boy oxygen would have made, I believe, a huge difference to the outcome."
Both Mr Henwood and Mr Haig agree the near-drowning highlights the importance of first aid training. "Although I now work within the corporate administration arm of St John, I spent many years training ambulance staff, including the paramedics," Mr Henwood said.
"I believe everyone should hold a first aid certificate."