Aaron Kerr cannot talk or walk, but his mother knows what he would say if he could speak about his road racing. Sandra and her husband, David, push their 18-year-old son in a custom-built Hoyt running chair in races across the UK and Ireland.
The specially-adapted wheelchair was developed by American Rick Hoyt after he pushed his son, Rick, who has cerebral palsy, in a five-mile benefit run in 1977 for a lacrosse player who had been paralysed in an accident.
That night, Rick told his father: "Dad, when I'm running, it feels like I'm not handicapped." Now legendary in the States, Rick went on to compete in cycling races, sitting in a seat in front of the bicycle, and in swimming events, in a special boat, as his father swims.
Sandra (43), explains: "The Hoyts have become friends and we admire them so much - I'm certain Aaron feels the same way as Rick did after his first race. Running gives him so much pleasure; he can go at the same speed as everyone else in his chair and he gives people hugs and high-fives as we go along."
From Annahilt in Lisburn, the Kerrs are regulars on the local running scene and an inspiration to all who meet them. Aaron, who has cerebral palsy, epilepsy and a rare chromosome disorder, also suffered from renal failure, aged 13, and received a kidney from his dad, David (41).
David cared full-time for Aaron until recently, when he swapped roles with Sandra to take up a job as a courier for the postal service. A former primary school assistant and care worker, Sandra is well qualified to look after Aaron, who requires round-the-clock assistance with his personal care and feeding.
"He needs help with everything, really, and I've to give him his medication; it's pretty full on," Sandra admits. "I started running alone to get my head showered, when the carer came in to give me a break, and that's originally how Team Kerr was born."
Sandra had been running for a few years, with David and Aaron watching from the sidelines. When they came across the Hoyt running chair online, they immediately realised it would be a wonderful way to get Aaron out and about in a family activity.
The chair came at a cost of £4,000, and Aaron was the first person in Europe to take delivery of the unique invention which, for some time, has been transforming the quality of life of disabled people across America.
"We started to fundraise and did a lot of sponsored walks," she recalls. "Friends and strangers helped us out and we finally were able to get the chair last October. It is priceless in terms of Aaron's quality of life. We don't know his life expectancy. As he's had a kidney transplant, we have to keep that stable. He will always have cerebral palsy; it's just a matter of maintaining his health."
Sandra, from West Sussex, and Ulsterman David met as teenagers in England. They moved to Lisburn in 2001, when Aaron was a toddler, knowing from his birth that he had a kidney defect and that a transplant would be inevitable. When dialysis became necessary for Aaron, David was relieved to be a suitable match and able to donate one of his kidneys.
Father and son came through the life-saving surgery in 2010 with no complications and Aaron has been thriving ever since.
"David never hesitated - Aaron is our son and we would do anything for him," says Sandra. "If he is smiling, we're smiling. Nothing was guaranteed, but thankfully his results were fine and all his check-ups since have been good."
Since then, the Kerrs have competed in everything from 5k runs to marathons, and use their profile to help raise funds for the Renal Unit at The Royal Belfast Hospital for Sick Children, where Aaron had his kidney transplant. They have also participated in runs for Born2Run, an events company which organises running events all over Ireland, in areas of outstanding natural beauty. The Belfast Telegraph has teamed up with Born2Run to provide a series of woodland runs at six venues in the province called Run Forest Run - the first of which is a 10k on Saturday at the Mary Peters Track, Minnowburn.
Sandra says: "We are good friends with the people at the Born2Run group, and they support us 100%. We understand that some of their races aren't suitable for us because of the terrain (forest runs), but where they can adjust their courses, they will, making them fully inclusive. Wherever we cannot run, we volunteer for them.
"We're also all members of Marathon Club Ireland - Aaron is the youngest member. You can only join this club once you have completed a marathon. Our club is very supportive of us and even adjusted its course to make it accessible, so that we could take part."
The family celebrated their first anniversary on Monday as Team Kerr at the Dublin marathon, their eighth this year. They have also completed 10 half-marathons this year.
"We keep reasonably fit and I work out in the gym in Lisburn and run along Belfast Lough at Jordanstown," adds Sandra. "Our lives revolve around running. It's our way to switch off - there's no disability when we're running; no issues of any kind. You're totally at ease with everyone else.
"Other than that, David and I get out to the cinema or for a meal occasionally."
Like so many fans worldwide, the Kerrs love watching the addictive Emmy award-winning series, Breaking Bad, which features a young actor with cerebral palsy (heart-throb RJ Mitte, who plays Walter jnr). And it appears Aaron has his fair share of female admirers.
"He's so happy and good natured, girls like him - wherever he goes, he gives them hugs," laughs his mother. "He's a very loving person, and so easy-going and laid-back; he takes after his dad. He does have the odd teenage strop, but nothing like his older sister, Holly (21), used to.
"He doing really well - all the fresh air is helping his immune system and keeping him fit and healthy, and he's sleeping better at night. He has made so many friends through running; we all have. Aaron's a bit of a celebrity in the running community. He loves the attention and he has really come out of his shell because of it. He's really is a completely different young man now."