A message on her Instagram page said Ms Mandela went into hospital on 18 September for treatment for metastatic cancer, which was on her hip, liver, lung, pelvis, brain and spinal cord.

"Recent scans revealed significant disease progression including fibrosis in the lungs as well as several emboli," the statement said.

"Zoleka passed away on the evening of Monday, 25 September, surrounded by friends and family. Our sincerest gratitude to the medical team that took care of her."

Ms Mandela had widely documented her cancer treatment in recent years, as well as being open about sexual abuse in her childhood, and addiction to drugs.

The South African was diagnosed with cancer when she was 32, but was in remission when the illness returned later.

She was also a road safety campaigner - her 13-year-old daughter died in a car accident in 2010.

She was the daughter of diplomat Zindzi Mandela-Hlongwane, who was the daughter of Nelson and Winnie Mandela.

Last week Ms Mandela posted a video of herself laying on a pillow, with a message saying she was "still treatable", followed by: "I'm off to bed".

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In 2022, Mandela revealed a further cancer diagnosis, writing: "I don't even have the words to articulate my thoughts and feelings, the words to describe how scared I am right now. What do I tell my children? How do I tell them that this time around, I may not get to live my life as a survivor? How do I tell them everything will be okay when it's not?

"I'm dying... I don't want to die."

She is survived by her four children.

The Nelson Mandela Foundation said: "We mourn the loss of a beloved grandchild of Mum Winnie and Madiba and a friend of the Foundation.

"When her inspiring memoir When Hope Whispers was published, she graciously signed copies for all our staff and ran a leadership session for the staff around the book.

"Zoleka was a tireless activist for healthcare and justice. Her work in raising awareness about cancer prevention and her unwavering commitment to breaking down the stigma surrounding the disease will continue to inspire us all.

"Our thoughts are with her family and friends at this most difficult time. Hamba kahle Zoleka, we will remember you."