Image copyright Getty Images Image caption Nkosi Johnson died in 2001

Nkosi Johnson was only 12 years old when he died after having Aids. He was born with HIV in Johannesburg, South Africa.

At the time he died in 2001 Nkosi was the longest-surviving child born with HIV. On Tuesday, which would have been Nkosi's 31st birthday, Google is paying tribute to him by having him as their homepage doodle.

Nkosi's mum was also HIV positive and became too ill to look after him, so he was adopted by a public relations officer from an Aids care centre.

HIV stands for human immunodeficiency virus and it targets the immune system. It can stop your body from being able to fight infections and disease if treatment isn't started soon enough.

In 1997, when Nkosi was just eight years old, his name became known when a local primary school near where he lived refused to take him as a pupil. It was because of his infection.

It caused huge political issues for South Africa, which forced changes to the law there. New anti-discrimination policies were put in place and that stopped children being banned from schools based on their health.

Image copyright Getty Images Image caption A picture of Nkosi at his home not long before he died in 2001

After the law changed the school allowed Nkosi in and he started to campaign for other children with Aids.

His step mother also helped him set up Nkosi's Haven. It's a non-government organisation helping to support mothers and children whose lives have been impacted by HIV and Aids.

As a result of his campaigning Nkosi became a key-note speaker at the International Aids conference in 2000 when he was just 11.

At the opening event he said: "Care for us and accept us, we are all human beings. We are normal. We have hands. We have feet. We can walk, we can talk, we have needs just like everyone else. Don't be afraid of us - we are all the same."

Nkosi died one-year later. Four years after that, to honour his efforts to raise awareness of the disease, the International Children's Peace Prize was created.

Since Nkosi's death there have been positive changes in trying to create a more accepting South Africa.

Media playback is unsupported on your device Media caption The women changing South African Rugby

The South Africa rugby team that won the 1995 World Cup had only one black player. By 2019 there were 12 in the squad with Siya Kolisi as the first black captain.

"This is the momentum you've got to use," he recently told Newsbeat. "Hopefully we can do stuff right now that could mean change for decades."

He's now inspiring more young black players to take up the sport, including girls.

Gabi and Tshepo are a young couple who would have broken the law in South Africa 30 years ago.

Inter-racial relationships were banned under apartheid law, which forced communities to live separate lives. Now they say their parents are supportive of their relationship, but Tshepo admits it's still quite hard for his grandmother because of the discrimination she faced.

"It's very difficult to go from being treated as a non-human basically, to having your grandson have a relationship with someone whose grandfather was above you."

As a couple though, they say it's up to them to change society.

It's now 25 years since the end of apartheid.

It changed when Nelson Mandela - who fought for the rights of black people in South Africa - became the country's first black president.

Nelson Mandela's great-granddaughter told Newsbeat she thinks he'd have liked South Africa to be more progressive in 2020 than it is.

"I know he wouldn't be 100% happy - but I also know he predicted a lot of what is happening right now," she said.

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