Haven Shepherd kneels on the school diving board, takes a deep breath and launches herself into the pool.
“When I'm in the water I feel completely free, I get to feel completely myself.”
The pool gives Haven respite from her prosthetic legs. Wearing them all day can be “exhausting”, the 15-year-old says.
It’s a long way from her training pool in Carthage, Missouri, to the hut in rural Vietnam where her father tried to end her life.
Haven Shepherd was born Do Thi Thuy Phuong on 10 March 2003, in Quang Nam province.
When she was just 14 months old, her father made a deadly decision. He entered their hut and strapped himself and Haven’s mother to a TNT explosive device. They held Haven between them.
The force of the explosion killed both her parents instantly and threw Haven more than 30ft [9m] from the hut, local reports at the time said.
“I survived something so dramatic - I wasn't supposed to live,” Haven says.
According to local media reports, Haven’s father was married to someone else and had other children. When Haven’s mother discovered this, she is reported to have threatened to leave him and he decided to end all their lives.
Haven has been told a different story, passed down by her grandparents. Their account was that, desperate at being unable to marry, Haven’s parents decided together to detonate the bomb.
What we do know is that Haven was found burned, shrapnel embedded in her head, and her feet mangled. But still alive.
Haven smiles as she recalls being called “the miracle child” as she grew up. But she remembers very little of her life in Vietnam.
She was rushed to hospital by her grandmother, and although it was a long motorcycle ride, across mountains and jungle, she didn't go into shock.
Once in hospital, both her legs were immediately amputated beneath the knee to avoid infection. She spent more than a month receiving treatment.
Her grandparents’ distress was compounded by their poverty.
Unable to pay for treatment themselves, they had to rely on donations from other patients’ families to help pay for her care.
“We hope you readers can help with this heart breaking case,” ends a local newspaper report from the time.
As Haven lay in hospital, more than 8000 miles (13,000km) away Shelly and Rob Shepherd were grappling with a dilemma.
The couple led a busy life in a small town in Missouri, US, raising their six children and running a family flooring business.
But Shelly couldn’t shake the feeling that their family was not complete.
“We had heard a speaker talk about international adoption, and the astronomical amount of children in the world that needed a home. I sat there telling myself that could never be us. Why would we? We had six biological children.
“Then the next thought was: ‘Why not us?’ From that point on I couldn’t rid myself from the feeling that we were absolutely supposed to do this.”
But for her husband it was not so simple.
Rob was still deeply affected by a fatal accident he had been involved in with his brother Terry in 2000.
They had been travelling home from a company picnic, with a dunking machine that had provided the afternoon’s entertainment strapped to their vehicle.
They misjudged the height of the game and the top of it struck a tunnel. The structure gave way, and Terry was crushed by the roof of their truck. He died instantly.
Rob and Shelly were a couple with a strong faith and had always opened up their home to other children - hosting and even fostering children for periods of time. But Rob just didn’t feel in the right frame of mind to go ahead with an adoption.
Eventually Shelly managed to convince him, and shortly after their decision the couple were invited on a trip to Vietnam with Shelly’s school friend Pam Copes and her husband Randy.
Pam and Randy had also suffered a terrible tragedy. In 1999, their teenage son Jantsen had died suddenly from an undetected heart ailment after football practice.
Pam and Randy cite a visit to Vietnam, where other friends had opened an orphanage, as an invaluable part of their own healing process.
They went on to help street children in Vietnam, using Jantsen’s memorial money to set up a foundation called Touch a Life.
Now the couple wanted Shelly and Rob to travel to Vietnam with them to help facilitate the adoption of a Vietnamese baby they had read about on a previous trip. That baby was Haven.
Haven’s grandparents had explained they were too poor to care for her, and wanted Pam and Randy to take her into a shelter they had opened for disabled children in Vietnam.
But Pam and Randy felt this was not the best place for her. There were not a lot of prosthetics available in the country.
They arranged for Haven to be adopted by another family in the US.
Shelly decided to take up her friends’ invitation to travel to Vietnam and help with the adoption. She thought the experience there would help her and her husband understand the needs of the world’s children.
But while they were there, something unexpected happened.
“We didn’t know then that we’d fall in love with her,” Shelly says.
It was October 2004, and the Copes and the Shepherds had travelled to Da Nang on Vietnam’s coast. They were then driven by van and finally motorbikes to a small village high in the mountains and thick jungle. It was there that Haven lived with her grandparents.
Shelly remembers with complete clarity the moment she met the baby for the first time.
“Her sister brought her up and I just put my hands out to her and she just put her hands out to me and at that moment it was like we both knew.”
Back in Da Nang, as they walked on the beach the following morning, Haven seemed to want Rob to carry her all the time. The couple started to realise that she was beginning to feel like their own child.
But just a couple of weeks later, once the paperwork and visas had been processed, Haven was in the US with her new adopted parents.
Shelly had expected to feel inspired by the trip to Vietnam. In fact she returned heartbroken.
“That moment where Shelly handed the baby over just about killed her,” recalls Rob. “But at the same time that was what we [had] agreed to do.”
And then, six days later, Shelly received a call from Pam. She told her that the other family had decided that they weren’t the right fit for her.
In just a matter of hours Haven was reunited with the Shepherds.
Now 15, Haven describes 19 November 2004 as her “gotcha day”.
“It’s the day when you are brought home to your family”.
Shelly, her voice breaking, says: “When she came back through the door our family was complete.”
She says her other children were fully supportive of the decision to adopt Haven.
“I think because we've been a big family, I always focused on teaching the kids that love is always multiplied, it’s never divided. So when you add another child, it just means we have a whole lot more love to share with each other.”
Among the open fields and expansive skies of their Midwest town, the Shepherd house is hosting a family breakfast. The living room is full of the noise and chaos of 13 children. Toddlers run across the room while older siblings discuss an upcoming wedding, laughing and joking.
Haven lies in the middle of the carpet as her nieces and nephews crowd around. One takes her arms, while another playfully lifts her by her prosthetic legs to swing her back and forward. Haven shrieks with laughter.
She says she loves being part of such a big family. Her siblings ranged in age from seven to 21 when she was adopted.
“I had four older sisters and I was always in their make-up, always dressing up just to be like them. I think that really shaped me because they were such great role models in my life.
“And, you know, growing up with a bunch of high schoolers - that was really fun. I got to eat breakfast for dinner a lot of times after a big dance and just had a really great childhood.”
Haven was five years old when she first asked Shelly how she lost her legs.
Her mum was lifting her out of the bath and wrapping her in a towel. Shelly told her the story.
“Well that was stupid,” Shelly says Haven interjected. And then asked: “Where do you even get a bomb in Vietnam?”
It wasn’t something Shelly could answer, and her daughter, confident and unfazed, had already started to play.
The use of explosives to settle debts, family disputes, and even take lives is not uncommon in Vietnam, and often reported by the local media, says the BBC Vietnamese service. Some parts of the country are still littered with explosives left over from the Vietnam war, which ended in 1975.
Haven’s story has had a profound effect on her siblings.
One of her sisters, 31-year-old Haley, has gone on with her husband to adopt their own child - from DR Congo.
And they in turn have influenced Haven’s life choices.
“I went from track meet to volleyball game to basketball game. I was always surrounded by a very active household,” she says. “So I always knew I was going to be an athlete.”
Shelly, however, admits that she initially had a stereotypical view of her disabled child.
“I thought, ‘OK I'm going to have to give her alternatives to sport.’ I thought maybe she'd play the piano or she would want to sew - there's so many dumb things I thought.”
Haven initially tried running like her sisters, but the sweat on her legs made her prosthetics slip.
Finally, Shelly suggested they try swimming.
“It makes me feel really empowered,” Haven says. “[Growing up], I couldn't really do everything on my own, so it's like the first thing that I got to do by myself.”
She started swimming at 10 years old, and just two years later had joined a more serious swimming team that trained all year round.
After her 13th birthday, Haven’s racing times were such that the US Paralympic team started tracking her as a potential national candidate.
Haven says this meant it was no longer enough just to be “an OK swimmer”. She needed to add weights and more time in the pool to her training regime. Nowadays there are also trips to Colorado to swim at the Olympic Training Center.
Last summer, Haven travelled to Italy with other prospective US Paralympic competitors and the team won two gold medals.
“I got to wear the USA across my cap and that was super cool. I took a picture of it and said [to my friends and family] ‘it’s real, it’s real.’
“Swimming for your country means a lot.”
It’s just over a year until Tokyo hosts the next Olympic and Paralympic games.
For Haven, the honour of being chosen to represent Team USA would be “the peak of my life”.
Her coach Shawn Klosterman thinks she has a good chance.
“She isn’t afraid to do the work,” he says.
Final trials are just a few months before the Games so they know that the next couple of years are going to be “kind of a grind”.
Shawn also recognises that Haven is still a teenager.
“She's a good example that you can be a committed top level athlete working hard and still be a goofy kid, and the fun and the training can go hand in hand,” he says.
Haven says that she loves being with her swim team - friends who she jokes are her “four leggers”, referring to the fact they have all their limbs.
She says she hopes she is helping to teach them that “there's more Havens out there”.
Haven says she grew up with very few disabled people around her, but she was always secure with her disability.
“I had two choices,” she says. “I could have become a very insecure person that was having her feelings hurt all the time, or I could see it as, 'Oh, you're staring at me because I have really cool legs.' And I do.”
When she’s not training and being home-schooled, Haven spends time working as an ambassador for other amputees. She visits amputees in the military, talks at schools, and emphasises the benefits of being different.
The pressure on Haven as a role model and the growing attention she receives did become too much last year, she admits.
“I really had to find a balance between being 14 and being this story that everybody wants to have.”
For Rob, Haven returning to Vietnam is an important part of her journey.
Her maternal grandparents remain in the country and her half-sister has been in contact online.
The Shepherds plan to visit after the 2020 Games “to get that sense of where Haven actually comes from and what her parents were like“, Rob says.
But for now, Haven’s focus is on her 16th birthday. It will, however, be bitter-sweet.
Since Haven was adopted, she and Shelly have been almost constantly by each other’s side.
Every day they travel for an hour together to swimming practice, but Haven will soon be able to drive herself.
“I think I'm going to call her on the way home just to hear her voice, because I love my mum.”
When Haven reflects on her dramatic start in life, she says she feels no resentment towards her biological parents.
She says she uses her extraordinary story of survival as an inspiration.
“I definitely see that circumstance as a real reason why you shouldn’t just be moping around your whole life.”