South Africa celebrates Nelson Mandela Day on Saturday, marking the anti-apartheid leader’s birthday. This year is dedicated to the memory of Zindzi Mandela, his youngest daughter, who died earlier this week.

UN Secretary General Antonio Guterres is expected to deliver this year’s Nelson Mandela Annual Lecture on Saturday, with the theme, “Tackling the Inequality Pandemic”.

“Madiba was a morale giant of the 20th century,” said Guterres ahead of the lecture. “This year’s lecture takes place at a time when the world faces an unprecedented test as the Covid-19 pandemic threatens everyone, everywhere.”

On Saturday’s #MandelaDay & every day, Nelson Mandela’s words inspire us to “ensure that democracy, peace & prosperity prevail everywhere.” – United Nations (@UN) July 18, 2020

The lecture is intended to help in “stimulating dialogue on critical social issues”, according to the Nelson Mandela Foundation.

Nelson Mandela reminded us that: “As long as poverty, injustice and gross inequality persist in our world, none of us can truly rest.” We must be part of the quest for a better future of dignity, opportunity and prosperity for all people on a healthy planet.#MandelaDay – António Guterres (@antonioguterres) July 18, 2020

Mandela’s youngest daughter Zindzi was buried at a private funeral on Friday, following her death earlier in the week. She was laid to rest next to her mother, Winnie Madikizela-Mandela, who died two years ago.