At 92 years old, he is frail now and rarely receives visitors.
But living legend Nelson Mandela made a special effort to see an inspirational woman who has made history in her own right.
The father of the Rainbow Nation granted a rare audience to Michelle Obama during her tour of southern Africa this week.
CLICK ON PHOTOS FOR FULL GALLERY
Her globetrotting girls Malia, 12, and ten-year-old Sasha, looked pleased, if a little overawed when introduced to the anti-Apartheid hero, who wore one of his trademark patterned shirts for their 20-minute encounter.
He signed a copy of his latest book Nelson Mandela By Himself for the Obamas.
First lady Michelle had also invited her mother Marian, and niece Leslie, 15, and 19-year-old nephew Avery - the children of her brother Craig.
The family were viewing Mr Mandela's personal papers at his foundation headquarters with his wife, Graça Machel - who is a former first lady of Mozambique - as their guide when he unexpectedly asked them to drop by his home in a leafy Johannesburg suburb.
While it was Michelle's first encounter with him, her husband Barack met the freedom fighter during his tour of Africa in 2006.
The Obamas will also visit Soweto, the famous township which lay at the heart of the fight against white minority rule.
And their visit will include a tour of Robben Island, where Mr Mandela spent 18 years of his 27 years in jail, before they travel on to Botswana.
Memorable images from Malia and Sasha's trips abroad