Kirsti Miller has been a national sports star, prison guard and taxi driver. But now, she prefers a new title: Grandma Spice.

The trailblazing trans athlete announced her transition in 2000, while working as a prison warden in Broken Hill, Australia — an inland mining city located in New South Wales. Over the ensuing 20 years, she’s faced a lot of hardship. There’s been bouts of homelessness, depression and a brutal gang rape.

But Miller is still here, and she’s proud. In the second half of her life, she wants to be an inspiration to trans kids everywhere.

“I was a bit like The Spice Girls, I suppose,” she told me on a recent edition of “The Sports Kiki” podcast. “At first, I was Baby Spice and then Scary Spice and I was definitely Slutty Spice trying to find myself a bit. Now I’m Grandma Spice, and that’s probably the nicest Spice I’ve ever been in my life.”

Miller, 55, says she started playing rugby when she was four years old. She excelled immediately, and also became one of the best swimmers in her age group. Growing up, Miller, who was born in the city of Wagga Wagga, represented her home state in four sports.

She broke a litany of state records and made the state swim team. In 1979, Miller competed in her first Aquathon, a grueling event that comprises a 5-kilometer run and 800-meter swim.

In her teen years, Miller trained alongside world champions and Olympic athletes. She represented Australia in the modern pentathlon, an Olympic sport that’s really five wrapped into one: fencing, freestyle swimming, equestrian show jumping, and a final combined event of pistol shooting and cross country running. Her achievements in the pentathlon landed her a spot in Wagga Wagga’s Sporting Hall of Fame.

On the surface, Miller appeared to be the epitome of masculinity. She beat up boys in the boxing ring and was a force on the field. As an adult, she became a prison officer. It was all part of the shield.

“The day I was born, my father crashed the car because he was so excited to have Warren Jr.,” Miller said. “I cannot underestimate the expectations that my dad placed upon my shoulders to be his little man. And how I coped, I manned up in a big way and tried to make it go away.”

One time, Miller’s father literally put her on his shoulders, and it’s a memory that haunted her for decades. One night, when Miller was three or four years old, she says her dad was having a big party at their home.

As a joke, he put Miller in a dress, and hoisted her above is head for all of the guests to see. Though Miller didn’t know she was transgender for many years, she always felt something was different about her. The scarring experience prevented her from looking inward for a long time.

“I thought to myself, if I ever come out as who I am, I’m going to be laughed at,” she said. “So that incident turned into a 30 year recurring nightmare, every single day of my life.”

In 2013, Miller became the first transgender soccer player in Broken Hill.

At the start of the new millennium, Miller began her new journey as an out transgender woman. It was a big deal among her fellow prison guards. Prison officers aren’t exactly known for their warm and cuddly feelings.

Neither was Miller.

“I wasn’t just a prison officer. I was renowned as the toughest screw in the system,” she said. “I was renowned through the system as the toughest guy. So it was sort of like, I don’t know, Usain Bolt coming out as trans today in the running community. It was huge.”

When Miller came out, the news spread quickly, and all the way up to the commissioner’s office. Miller flew down to Sydney to see him, and within minutes, he was crying his eyes out.

He promised her that he would look after her — and he did.

“That was probably a real emotional day in my life, that’s why I’m a bit croaky right now,” Miller said. “But I’m really glad I did it, because the only way for transgender people to just dispel these beliefs about us is positive visibility.”

Though Miller was accepted within the confines of prison, the outside world was more of a problem. Miller returned to organized sports in 2013, becoming the first transgender soccer player in Broken Hill.

The players were fine, but the taunts from coaches and fans became increasingly vile and vicious. The dehumanizing experience is the reason why Miller is so passionate about trans inclusion in sports — and unapologetically outspoken on Twitter.

“I got asked to show my genitalia. I got, a number of times, accused of having AIDS,” Miller said. “I’m not going to give up on this until everyone can play the game and not get accused of AIDS.”

At first, Miller considered writing a report documenting her abuse. But then she thought back to her days as a prison officer, where she learned about the power of visibility.

That’s when Miller decided to drive a taxi, and introduce herself to the community one fare at a time.

It worked. Miller still lives in Broken Hill today, and everybody in town knows who she is. The relief feels euphoric.

“A lot of prison officers would say how hard it is for these people in segregation,” she said. “I would have swapped any time to get out of the inside imprisonment I had inside my head.

“It was far more stricter than what people, the murderers that were in these strict cellular confinements because they got an hour a day to escape. I never got a minute out of my whole life to escape gender dysphoria, until I got the day to come out as who I was. And that was like being released from jail.”

Miller wants every transgender person to feel what she’s feeling. That’s why she’s aghast at efforts to exclude trans people from any facet of life, including sports.

“I definitely didn’t transition to win medals,” she said. “I transitioned to survive. I wouldn’t be here now.”

And now that Miller is here as her true self, she’s making the most of her time, and wants to share her story with as many people as possible.

She doesn’t want any transgender boy or girl to feel alone.

“I see being trans as being a bit of a superpower,” she said. “I’m lucky to be who I am and I want every child that’s growing up trans now, might be thinking what’s the future going to be like? It’s going to be all right.”

You can follow Kirsti Miller on Twitter, @KirstiMiller30.

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