In December last year, he won the Special Olympics Attitude Award honouring athletes who have risen above challenges and whose involvement highlights the values of physical activity and wellbeing.
Hamish, who finished runner-up as Disabled Athlete of the Year at the 2020 Hawke's Bay Sports Awards, is currently training for the national swimming championships in Hamilton at the end of 2021.
In 2018, Hamish also took up football after watching his twin play at club, regional and national level, winning a trophy at the Hawke's Bay Special Olympics prize-giving the same year.
Hamish's mother, Stephanie, said having his twin brother as his role model has led him to where he is today.
"He's always wanted to be like his brother, do sport like his brother, compete for his school like his brother and get a job like his brother," she said.
"He'd would watch his brother, want to give things a go, gain confidence and then join in when ready."
Alongside sport, the inspirational young man developed a passion for public speaking sparked by a school assignment in 2017.
The former Clive School, Havelock North Intermediate and Havelock North High School student said while nervous to speak in front of his peers, the speech was a great success and ignited a new hobby.
"I had to do a speech about the Duke of Edinburgh and my experience with the bronze award, and I did it and nailed it," he said.
Stephanie remembers the elation her son felt after achieving his first three NCEA credits with his speech.
"He came home with the biggest smile on his face, like the Cheshire cat," she said.
Hamish's confidence continued to grow, going on to gain Duke of Edinburgh Silver and Gold awards – one of only two at his school to do so last year.
In March 2020, Special Olympics regional sports co-ordinator Jemma Drake proposed an idea that would challenge Hamish more than ever before – a 25-minute speech at the opening of the Duke of Edinburgh Special Olympics club.
Having never spoken in front of anyone outside his school or family, Stephanie was unsure how he would cope.
"I really did not know how he would go, but I needn't have worried," she said. "Having practised loads, he did his best performance ever in Wellington and blew everybody away."
Drake said she felt proud having witnessed Hamish grow in confidence since that day.
"I can't wait to see what's in store for him in 2021," she said.
Using his newfound confidence, Hamish's other passion, kapa haka, has also hit new heights.
"I did kapa haka last year and I invited some of my friends from the special needs unit," Hamish said.
After his encouragement, four fellow students from the special needs unit joined the kapa haka group and were recognised by the school for breaking barriers.
Hamish has attended the Kapa Haka Nationals in 2019 and won the Patu Award at the Sports and Cultural Dinner in 2020.
With twin brother Sam now at university in Auckland, Hamish took a leap into the working world, landing a job at Splash Planet as a park host.
"He's one of the team and we're grateful to Mahi for Youth and Splash Planet for seeing the potential, empowering him and giving him an opportunity," Stephanie said.
"It's been great seeing that he has purpose in his life and feels valued."
With summer drawing to an end, so did his job. But Hamish soon found voluntary employment at both Nimons and Gracelands Rest Home and Village.
On World Down Syndrome Day on Sunday, Stephanie said she hopes Hamish's achievements will let others see what is possible.
"Hamish is proof of what people can achieve when opportunities are given and barriers are removed," she said.
"There's always a way - it may be a different or longer road, but we can all get there."
