Mourners attend a memorial service for anti-apartheid activist Winnie Madikizela-Mandela at Orlando Stadium, in Soweto, South Africa, Wednesday, April 11, 2018. Themba Hadebe/The Associated Press ...

Madikizela-Mandela, left, attends the Dec. 10, 2013, memorial service for her former husband in Johannesburg. (Matt Dunham/Associated Press) ...

In this Dec. 10, 2013 file photo, Winnie Madikizela-Mandela listens to speeches during the memorial service for her ex-husband, former South African president Nelson Mandela at the FNB Stadium in ...

A man holds up a frame showing newspaper clippings of anti-apartheid activist Winnie Madikizela-Mandela during her memorial service at Orlando, Stadium, in Soweto, South Africa, Wednesday, April 11, ...

Caption: Winnie Madikizela-Mandela, left, Nelson Mandela's former wife, attends the memorial service for former South African president Nelson Mandela at the FNB Stadium in the Johannesburg, South ...