Explains mother Brigette Van Zyl why the then 4-year-old and brother Kyle, 14, took swimming lessons: "When we were in Auckland we lived close to the beach so she was like a fish to water."
Having had the measure of water at the Coast Swim Club, the youngster had no qualms about going under or floating on it.
But it wasn't until Van Zyl was 9 that her competitive trait started to emerge, although she gave up swimming for a year.
"People were shouting across the pools and I would stop, thinking that they were shouting at me," she says of when she was 7 at the AUT Millenium pools in Albany, although school work also was factor.
However, she moved to Northern Arena near SIlverdale, where Coast Swim Club is based, where 2016 rookie coach of the year John Gatfield honed her skills in groups of abilities.
"It was much better because it was like instructors swam with you."
Her preference for the butterfly discipline came when Laura Quilter, also a swim coach at Coast Swim Club, remarked on her technique, saying one day the youngster was going to be as good as her.
The New Zealand Commonwealth Games butterfly specialist, who is now 24, simply smiled when Van Zyl quipped: "No, I'll be better."
But South African-born Van Zyl, who emigrated to Auckland with her family when she was 3, laughs on reflection at her insular mindset, because she has a fair way to go in emulating Quilter.
She also favours freestyle, enjoying the thrill of speed over 50m bursts.
Van Zyl moved to Hawke's Bay in January last year with her family, including her father, Dion.
She first joined the Greendale club and then Napier Aquahawks but didn't find much traction with either of them.
In October last year she joined the Trojan club, where former Olympian Daniel Bell, of Hawke's Bay, inspires her as coach.
"I enjoy him a lot and he went to the Olympics so that's my dream."
Van Zyl trains six times a week, 90 minutes before classes as well as after school but rests on Sundays although her determination is undeniable in her success last month.
Three mornings a week the Year 7 pupil rolls out of bed at 5.30am trains and then has her breakfast in the car on the way to Twyford School.
"It takes me a while to open my eyes but I have a hot chocolate to wake me up."
Van Zyl, who also plays netball, believes dedication to training and competing at meetings will build her template for the Olympics.
What about diet?
"Well, I have a lot of McDonald's," she confesses amid laughter before her mother says whoever will become her dieticians will have their work cut out.
Next weekend she is competing at the Auckland Open Championship in Henderson where she hopes to break the 50m butterfly record of 31.69s for her age before she turns 12 in April. Her personal best is 32.79s.
Trojan clubmate Tobias Leiser, 11, clinched two golds, as many silvers and a bronze medal while Michael Lansdown, 12, came home with a silver medal and three bronzes.
Victoria Sullivan, 11, registered three PBs out of five races in her maiden meeting while Evie Skidmore, 10, returned with five PBs from eight races.
TERRIFIC TROJANS
The five Trojan Swim Club members who won medals or achieved personal bests in their respective gender age groups during the New Zealand Swim Festival (Wellington zone) last month:
■ BIANCA VAN ZYL, 11: 50m butterfly gold, 100m butterfly gold, 50m freestyle gold, 100m freestyle gold, 100m individual medley gold, 100m backstroke gold, 200m backstroke gold, 200m freestyle silver.
■ TOBIAS LEISER, 11: 50m backstroke gold, 200m backstroke gold, 50m freestyle silver, 100m backstroke silver, 200m freestyle bronze.
■ MICHAEL LANDSDOWN, 12: 200m breaststroke silver, 200m IM bronze, 200m freestyle bronze, 100m breaststroke bronze.
■ VICTORIA SULLIVAN, 11: Three PBs out of five races with the best of 7.41s in 100m breaststroke in her maiden regional meeting.
■ EVIE SKIDMORE, 10: Five PBs out of eight races with the best of 6.46s in 100m breaststroke.
