On his 91st birthday, Nelson Mandela is still making a difference.The anti-apartheid icon celebrated his big day in the company of loved ones at home in Johannesburg. South Africa’s President Jacob Zuma paid a visit. But, in an initiative called Mandela Day, the frail former statesman also appealed for others to be remembered – urging people to do good for 67 minutes today. That is the number of years since Mandela, who is affectionately dubbed Madiba in his homeland, first devoted his life to the fight against apartheid. On the Nelson Mandela Bridge, Johannesburg, resident Lorren Mabela explained that she was helping by taking part in a road safety campaign. “We believe by doing this, we will be saving people’s lives and, in a way, honouring Madiba,” she said. Nurse Thandiwe Gwinza said she had made soup after her nightshift. “I have made soup for the people and I have given them my old clothes.” Last year, the Nobel Peace Prize winner celebrated his 90th birthday on stage in London, two decades after the historic Free Nelson Mandela concert in the city. Finally released after 27 years behind bars, Mandela became South Africa’s first black president in 1994. He stood down after only one term but is still revered worldwide for his promotion of peace and the fight against HIV. In New York, singers including Stevie Wonder and Aretha Franklin are performing today for Mandela’s AIDS foundation.