Winnie Madikizela-Mandela should be laid to rest next to former President Nelson Mandela when she dies, jailed Abathembu King Buyelekhaya Dalindyebo has said.

“I believe you are still married, because in our records I do not have any such record in the kingdom that dissolves such a marriage, as mandated by our customary law,” he said in a letter read at a gala dinner in Johannesburg on Monday, in celebration of the struggle icon’s 80th birthday.

It was read by Nkosana (Prince) Langalibalele Mthunzi Ngonyama.

Dalindyebo said he wrote the letter from his dark prison cell. He said he would have loved to be at the dinner.

“You were there for me as a mother throughout my dark days, when I needed love and comfort in extremely dark and life-threatening days during the apartheid era.”

The king is serving a 12-year jail term in East London’s prison for kidnapping, defeating the ends of justice, arson and assault.

In his letter, he spoke of Madikizela-Mandela’s resilient spirit. He thanked her for staying with Mandela throughout the struggle for democracy. The couple divorced in 1996. Mandela initiated divorce proceedings in 1992.

“If it wasn’t for your strength and your spirit, you could have lost hope and have walked away, leaving Madiba hurting and struggling. Who knows, maybe he could have surrendered himself to the enemy and ceased to fight, but your smile saw him through his dark days,” Dalindyebo wrote.

He had been reading much about Madikizela Mandela’s life, including her book 491 Days , in which she documented her time in police custody.

He said he was thinking about his own children, asking himself if they were being harassed at school and making headlines about their father, a “jailed and disgraceful king”.

‘We want a woman president’

African National Congress (ANC) treasurer general Zweli Mkhize, party chairperson and National Assembly Speaker Baleka Mbete and ANC Women's League (ANCWL) president Bathabile Dlamini delivered speeches between performances on stage.

Dlamini thanked Madikizela-Mandela for steering the ANCWL through tough times

“We have already decided we want a woman president,” she said, referring to the ANC’s succession debate. President Jacob Zuma’s term ends in 2017.

Dlamini said the ANCWL was determined to use its power to get its preferred candidate to the top post in the ruling party.

Dlamini committed to helping the poor with study fees.

“As much as a child of a farm worker, a domestic worker, rural woman, or township woman is not able to pay school fees, we are going to support our children.”

Students have been protesting for free higher education since Higher Education Minister Blade Nzimande announced last Monday that universities could increase fees, but by no more than 8%. Poor students would not have to pay the increase.