Sarah Munt was in her mid-30s when she discovered she had an older brother who had been adopted out almost 50 years earlier.
It was 1972 and her mother was 17 when she faced a difficult situation and gave her son, Brett Wallin, up for adoption.
Discovering he existed came as a shock to Ms Munt, but a few months later they connected and have since forged a strong bond.
"I've found my best friend and Brett has found his," Ms Munt said.
"It's been the most exciting time in my life really to meet someone who is my brother, who I didn't know I had all my life, and to then find out he's my best friend and so similar to me.
"We finish each other's sentences."
This Sunday, having inspired each other, the pair will take on the 36th Ironman Australia triathlon at Port Macquarie, on the NSW Mid North Coast.
They will join more than 2,700 other athletes — including defending Ironman Australia champion Tim Van Berkel — who will tackle the 3.8 kilometre swim, 180 kilometre ride and 42.2 kilometre run.
Ms Munt was encouraged to take on the challenge after learning that Mr Wallin had completed three previous Ironman Australia events.
"Brett did his first Ironman when he was 36 and I will do my first Ironman when I am 36 and it's the 36th Ironman Australia event," she said.
A brother and sister unite
Ms Munt and Mr Wallin's path to friendship began when Mr Wallin decided to try to find his biological mother a few years ago.
"I always knew I was adopted, and my mother who raised me was always really open about it," he said.
"A few years ago, I am 50 now, mum really pushed it with me and said she thought it would be a good thing for me [to look for my biological mum] ."
After an Ancestry DNA test revealed his biological parentage, Mr Wallin reached out to his mother and the family were reunited in person at his Sydney home a few months later, surprising him on his birthday in June 2020.
"It was an emotional time," Mr Wallin said.
Mr Willis said meeting his sister had also helped him through a difficult stage in his life.
The pair were both facing personal and relationship challenges when they met and Ms Munt later moved from Victoria to share a place with her brother at Caringbah in Sydney's Sutherland Shire.
"I think we help each other in different ways. She calms me down and keeps me focused," Mr Wallin said.
"I was at a lower point in my life when Sarah came in… my marriage was not working too well and I was probably abusing alcohol a little bit.
"Meeting Sarah, she was so positive. When I am down in the dumps she always picks me up. I don't drink alcohol anymore.
"I would not be as strong as I am now if Sarah did not stand beside me and help me. Sarah saved me, I think."
'I just want to finish'
Ms Munt and Mr Wallin are looking forward to taking on the Ironman challenge this weekend and will be cheered on by their biological mother, and their own families.
"I don't really know what I am in for," Ms Munt said.
"I've been training hard, my coach says I am ready, Brett says I am ready, I just want to finish and run down that finishing chute and feel it."
"I have changed a lot in the past 12 months and a lot of that is because of Brett, he's always pushed and encouraged me. I have become a better person because of Brett.
"It's been the best thing that's ever happened to me."
Mr Wallin said he was looking forward to taking on the challenge with his sister.
"I am mentally as well as physically healthy again," Mr Wallin said.
"My goal is just to finish and support Sarah as much as I can as well.
"I will have one eye on my stuff and one eye on Sarah.
"I am really looking forward to seeing her cross the line."
