Over the years, the Guardian News has written many articles about this Macksville mermaid's feats.

Read about them here, here and here.

But last month Millie outdid herself in her debut at the NSW Senior State Age Championships at the Sydney Olympic Park Aquatic Centre.

Swimmers first had to meet a qualification time to be eligible to participate in events at the Championships, which ran from December 12 to 17.

Millie qualified for a remarkable seven events and competed each and every day of the Championships; by anyone's account she'd already accomplished a remarkable deal before she even dipped her toes in Sydney waters.

Up to 50 of the best swimmers in NSW squared off for each event, with the 10 fastest qualifiers from the morning heats progressing to the evening finals.

Millie swam eight Personal Best times and finished in the Top 10 of four separate events in the 12-13 Girls age group.

She finished fourth in the 100m Butterfly, fifth in the 400m Individual Medley (IM), and sixth in the 200m IM. But her crowning achievement was scooping the silver medal in the 200m Butterfly.

Her coach, Sarah-Jane Weir, was over the moon.

"It's an amazing achievement just to qualify for a final. But to medal is phenomenal - I couldn't be prouder," she said.

Her success is a consequence of her unrelenting commitment.

"Millie trains extremely hard - swimming upwards of seven sessions per week, and dry-land sessions on top," Sarah-Jane said.

All five of Millie's teammates also placed in the Top 10 for their events: "a remarkable result for regional NSW," Sarah-Jane said.

"It's nice for these guys to get some recognition after the sacrifices they make to be able to swim in the country. To get those results against kids that get to go home every night after competition is spectacular," she said.

"My athletes train out of a 20m pool at Harbour Swim School, Coffs Harbour, making these results even more spectacular.

Millie will now get the chance to make an even bigger splash at the Nationals which will be held at the Gold Coast Commonwealth Games pool in Southport in April.

"She wants to make an Australian team one day so I really hope it happens for her. She's very, very talented," Sarah-Jane said.

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