The 24-year-old, who missed out on the Rio Games through injury and feared she may never make a Paralympics when her event was reclassified a year later, produced a storming performance to win the S5 100m freestyle in Tokyo.
It is just five years since she was told she may never be able to swim competitively again due to her condition, generalised dystonia, worsening.
The condition causes spasms and seven-times world champion Kearney was left fearing she would never compete at a Paralympics.
However, she fought back and also claimed a silver medal yesterday in the S5 200m freestyle yesterday - just missing out on gold after tiring on the last length.
“It means a lot to me because it shows other people with dystonia and all disabilities you don’t have to give up,” said Kearney, after her silver medal success yesterday.
“You can achieve what you want to achieve, you just have to adapt and it might take longer.
“There were many times when I almost gave up. When I started to withdraw, there were many times when I was told I wouldn’t swim again and it took me so long to get back into the pool.
“I thought it would be better not to swim than learn I couldn’t. But my mum pushed me, because she knew I would find a way.
“If it wasn’t for her, I wouldn’t be here.”
Fellow Aldridge swimmer Ellie Simmonds, who carried the flag for Team GB at the opening ceremony in Tokyo on Tuesday, came sixth in the SM6200 individual medley today.
The race was won by fellow Team GB swimmer Maisie Summers-Newton.
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