A grieving mother who lost her "gentle giant" son at just 21 years old has urged other young people to get their hearts checked for abnormalities.
Mason Ah-Mun, described as a "fit and healthy lad" who loved playing football, collapsed just yards from his home on March 11, 2020 and was found by a passer by who called an ambulance.
Despite the very best efforts of paramedics at the Welsh Ambulance Service he was pronounced dead before he had even reached the University Hospital of Wales in Cardiff.
It was later discovered that Mason, from Penarth, Vale of Glamorgan, had an extra thick layer of muscle around his heart which is likely to have contributed to his sudden cardiac arrest.
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"They told me it was like turning off a light switch," said his devastated mother Maxine Ah-Mun.
"I'm not just saying this because he was my son, but Mason was genuinely such a really, really lovely lad. He was a very calm person and always had time to talk to people.
"He was a gentle giant; a big, handsome guy who had a very protective nature."
Maxine said there was a history of heart problems in the family, particularly among the men. But she never thought she would lose her son at such a young age to sudden arrhythmic death syndrome (SADS).
She added: "When we look back we've had bypasses, heart attacks, everything. Even my cousin has just had a stroke at 40 due to his heart. I would urge everyone to go and get themselves checked if they have a family history."
Maxine, a mum of two, said only 10 people could attend Mason's funeral as it coincided with the very start of lockdown.
"I have a very strong family support network, and to only be able to choose 10 people was so hard. Everything about the funeral was rushed and it was nothing like I wanted it to be. It was awful," she admitted.
In an attempt to cope with the unrelenting grief she faced, Maxine decided to put all her energy into creating a mobile phone app called Moving Around Safely, or MAS app for short.
As well as promoting businesses that support equality and are safe from discrimination, it has a section which helps people locate their nearest defibrillators.
"There is only around a 15-minute window [when someone has a cardiac arrest], so the app will help access the defibrillators quicker and hopefully save lives," she said.
"Mason always told me he wanted to create an app and then retire, so when I was grieving I had this sudden idea - and I'm now working with a company on its development. It will cost around £8,000 to get up and running."
To raise money for the app, one of Mason's former class mates from St Cyres School in Penarth, Verity Tucker, has decided to run 30km with her friends from Llanharan in Rhondda Cynon Taf to Cardiff Bay on May 1.
Since she set up a JustGiving page a month ago, more than £5,600 has been raised. To donate please go here.
Maxine said: "Verity needs to be recognised for this selfless act of pure love and friendship. We're all truly grateful to her and so many others. Mason's friends are all amazing - and they still phone me to this day to ask how I am.
"Any money made from the app will have a percentage put back into the charity Welsh Hearts and SADS to get more defibrillators located across the country and towards the maintenance of them."
