His twin Curtis and older brother Jarrad read poems, while his former youth rugby coach Tom Wiggins also paid tribute.
After the service his coffin was taken for a lap of the rugby club, a place he had spent many happy years playing the game he loved.
In a powerful tribute, former team-mates and friends formed a guard of honour and clapped as his family carried Kieran out of the rugby grounds one last time.
Shortly afterwards, the funeral cortege proceeded for interment in Ballee Cemetery.
Tom Wiggins, honorary secretary for Ballymena Rugby Club, had coached Kieran when he was 11 and again when he returned to play in the under-19s squad.
"Rugby's a big family and to lose somebody so young is just terrible really," he said.
"He was a tremendous young lad and he actually nearly lived for Rugby. He was a tenacious, hard and committed player and he just loved the game and that's why it was his wish to leave the rugby club one last time."
He said for his team-mates, saying goodbye at the club "was massively emotional for them".
"I'm talking to boys who maybe haven't been out here for five or six years, they wouldn't miss it because they just wanted to see Kieran sent off in the right way."
As a respected player in the number 7 position, Kieran was known to have formed a formidable partnership on the field with his twin brother Curtis.
"I used to call him twin because I could never tell the difference between Kieran and Curtis," recalled Tom. "I'd say 'twin, stop that boy doing that'. The number 10 would pass to 12, 12 to 13 and Kieran would hit the 10 and put him on his backside. Then he'd try and get away before the referee knew who did it, he was just a typical 7."
Kieran was in his second year at the University of Lancashire studying sport science when he was diagnosed. While there, his love of rugby continued and he played weekly for Hutton Rugby Club.
Three of his Hutton team-mates travelled to Ballymena to say goodbye. Jim Gouldon (39) from Preston said: "It was a really good send-off, it was just nice to see so many people there who cared about him."
Laughing, he added: "He gave me a lot of stick for being an old man, being twice his age.
"But he was a brilliant guy.
He was just funny and always seemed to be a happy bloke."
Sam Biggs (27), also from Preston, called Kieran "a genuinely nice bloke".
He added: "We just wanted to come over and show the family our support and show he was cared about over in England as well."
Rob Aird (37) remembered picking Kieran up every week from university for games.
"It was an emotional time (during the guard of honour)," he explained.
"In rugby we clap players off the pitch, so it was good to give his final goodbye as you would have done if he'd been playing today."
Ballymena players Jordan Millar and Simon Crooks, both 19, said they had happy memories of their time playing with Kieran.
"It was good to see a good crowd out, the big man deserves it," said Jordan.
"When you were playing, even at training, you always looked up and saw the Bowes twins wrecking boys. They loved it, just lived for it."
Simon added: "Whenever he passed away we always knew he had a big soft spot for the rugby club and it was good to get him back here where he spent most of his time.
"He got a good final farewell at the gates."
Despite Kieran's illness he had remained fighting till the end.
Last summer he managed to climb to the top of Slemish Mountain.
"He never let (his illness) beat him," said Jordan.