He said his aunty got him into running a couple of years ago and his whole family was right into sports.
Hewitt said his two younger siblings played sports and his twin brother Justin was also a good athlete. "He is stronger than me but I am faster than him."
While Hewitt's main discipline is running, he is also a fine long jumper. "It's because I'm fast and have long legs."
Hewitt said he hoped to win more gold medals at the secondary schools nationals again next year. Students with a disability can compete at the nationals until they are 20.
He also has high hopes of one day attending the Special Olympics World Games as a runner.
He said next year he wanted to try to improve as a sprinter. "I will keep on training and get my legs stronger."
Hewitt said one of the things he enjoyed about taking part at the nationals in Wanganui was meeting new friends and also encouraging other athletes.
"One of the other athletes said he was not a good sprinter so I encouraged him to make him feel better, and just told him to try it out."
Hewitt's results at the nationals included 60.08 seconds in the 400m, 26.45 seconds in the 200m, 13.19 in the 100m and 4.85m in the long jump.
Young Western Heights student Brooklyn Tomo, 13, also attended the nationals, finishing seventh in shot put and 13th in discus.