Nelson Mandela in hospital as South Africans pray
Prayers have been said in churches across South Africa for former President Nelson Mandela, who has spent a third night in hospital for treatment for a lung infection.
Officials have provided no update since Saturday when his condition was described as serious but stable.
However, the BBC's Karen Allen in Pretoria says relatives who visited him on Sunday appeared in positive mood.
Mr Mandela, 94, was admitted to a Pretoria hospital early on Saturday.
The presidency said he had been ill for some days.
It is the third time this year he has been admitted to hospital.
Hundreds of worshippers attended Mass on Sunday at Soweto's Regina Mundi church, famous for its role in the anti-apartheid campaign.
"I think it's just a natural experience that everybody wants to hold on to him as much as possible," acting priest Father Sebastian Rossouw said.
"He's always in our prayers."
Our correspondent says there is a sense of calm across South Africa, and also a quiet hope that the man who led the fight against apartheid may regain his strength once again.
While the absence of any official updates did little to help the speculation, she adds, many took heart from a visit by Mr Mandela's daughter, Zindzi, who said that her father was "well" and "a fighter".
Mr Mandela's wife, Graca Machel, cancelled a scheduled appearance in London on Saturday to remain at her husband's bedside.
The South African broadcaster SABC reported that a car which brought another daughter, Makiziwe, to the hospital on Saturday was seen again on Sunday.
On Saturday, presidency spokesman Mac Maharaj said that although Mr Mandela was again suffering from pneumonia, he was breathing on his own - "a positive sign".
South African President Jacob Zuma has continued to attend engagements but has indicated that he will visit Mr Mandela if doctors advise him to do so.
Nelson Mandela served as president from 1994 to 1999.
He was previously imprisoned for 27 years, and is believed to have suffered damaged lungs while working in a prison quarry.
He contracted tuberculosis in the 1980s while being held in jail on the windswept Robben Island.
He retired from public life in 2004 and has been rarely seen in public since.
Mr Mandela was receiving care at his Johannesburg home when his lung problems flared up again.
He was admitted to hospital after his condition worsened at 01:30 on Saturday (23:30 GMT Friday).
British Prime Minister David Cameron has said Mr Mandela is in his thoughts, while the White House has also sent good wishes.