(CNN) For a generation of athletes in the Swarts family, it seemed as though the Olympic dream wasn't supposed to happen.
Odessa Swarts, a track-and-field athlete who competed provincially in South Africa, couldn't qualify for the national team, let alone the summer Olympics, because of her ethnicity while the country was under apartheid.
She never got the chance. But her son is making up for it.
Swarts' son, Wayde van Niekerk, won gold in the 400-meter sprint Sunday in Rio with a world-record time of 43.03 seconds. The record in the event had been held by U.S. track and field legend Michael Johnson for over 15 years.
"I was totally blind on the outside lane. I remember hitting the 200 mark and still feeling there's not much people around me, and I got to the last 100 meters and I'm like, 'I still don't feel anyone close to me,'" van Niekerk told CNN in an interview.
It was such an impressive moment that the world's fastest man, Jamaican Usain Bolt, climbed the stands of the stadium and embraced him.
But 24 years ago van Niekerk's path to the Olympics, and even his ability to have a normal life, were very much in doubt.
"He was born (prematurely) at 29 weeks. I went into labor at 28 weeks and there was no stopping him," his mother told CNN.
"He was very skinny ... he was just flesh and bone. We were told if he makes it through the first 24 hours, he will have a disability," Swarts said. "Today he's standing on the world stage. Who would have ever thought?"
Van Niekerk has given one of the standout performances of these Rio Games. But for his mom it wasn't about missed opportunities for herself.
"If I had all those opportunities, my son wouldn't be here today. That era wasn't meant for me -- it was meant for the generation that's coming through now," she said. "We never had the opportunity to be on the world stage, as our athletes are doing now. God had a plan for this era."
For van Niekerk, his record-setting race is much more than a point of family pride -- it's a symbolic moment for post-apartheid South Africa.
"When I got over the finish line, I felt like a proud South African, not a proud colored South African," he said. "I'm happy and proud to be an ambassador for my country."