Both families involvement came about when a friend of Lloyd's entered him for his third Coast to Coast as a two-day individual without telling him.
Bemused, the younger Steward decided to stay in it only if his father, who he has entered multisport events with before, came along.
Athol Steward decided he could enter the team race.
"I called on my strongest and most reliable friend," he said.
"And he wasn't available so he called me," Brett Watson laughed.
The senior Watson then thought his own student son Angus, a student in Christchurch, would also like to join them.
"A little bit of coercion and a little bit of pressure," the senior Watson said.
Angus Watson looked at the fees and decided he would like to tackle the challenge of the one-day race pitting himself against heavyweights like Richard Ussher, Dougal Allan and Braden Currie.
"It's quite a competitive field," Angus Watson said.
"My goals, I'd like to come home and have energy left for the cycle into Christchurch.
"Up until 6pm, the police close the traffic lights, so I'd like to get through by then."
Unlike their fathers, the younger men have had the opportunity to train on-course, going for runs through the stunning Arthur's Pass and kayaking on the Waimakariri.
As a first-timer, knowing the river has calmed down a bit in the warm weather, Angus Watson said he was now enjoying the white water. "Early on it was a complete terror."
In preparing for the tough mountain run, Athol Steward is leaning heavily on the advice of his son who knows from experience that given the weather, the route can change from year to year.
"He said it's not a lot of running, most of it is clambering.
"If you get the route wrong it becomes a whole lot more difficult.
"That's what people say about the race on race day a lot of your preparation is out the window."
Brett Watson also has experience on the Waimakariri and thinks "it will be great to see it all".
Coming from the medical profession, it is Athol Steward who has been responsible for sorting out their diet in training and for the race a combination of carbohydrates, protein formula and even fat as a source of energy.
"Slightly under-trained and slightly overweight can be a little ideal," he said, recalling times when cold and wet weather has been harsh on the contestants.
All of them will have a big support crew of family and friends.
The three newcomers do not know if they will enter the famous race again right now it's something to be ticked off the list.
However, they are aware from those who have told them of the Coast to Coast's propensity to draw people back, due to the unique experience of the race.
More than 600 competitors will take part in this year's edition of the gut buster.