Archbishop Emeritus Desmond Tutu and his wife, Leah, who have been married for 63 years, celebrated their anniversary at Tygerberg Children's Hospital.
The couple spent Monday at the children's medical facility.
According to the Desmond and Leah Tutu Legacy Foundation, the Tutus have been active patrons of the hospital for the past 18 years.
They have also raised funds to contribute to the hospital's Retcam, which screens high-risk infants' eyes and prevents blindness, as well as equipment for the paediatric intensive care unit.
During their visit, the hospital presented the Tutus with winter scarves as a token of appreciation.
As the Stellenbosch University's teaching hospital, the children's hospital is responsible for the provision of tertiary medical care to about half of Western Cape children in need, as well as some children from further afield.
Razaan Bailey of the foundation said that the Tutus have always had much love for the children's hospital.
Bailey added that the Tutus regularly told foundation staff over the years that they found the commitment and compassion of the people at the hospital "extraordinary and exhilarating".
Tutu nearly died of tuberculosis when he was young, after overcoming polio in his infancy.
He was also unable to study medicine owing to financial difficulties, but fulfilled his dream by joining a class of senior medical students at the hospital for some practical training a few years ago.
Leah studied nursing after completing a teaching qualification.
"To honour its founders' love and respect for the institution and those who make it work, the foundation had executed several festive season projects at the hospital, sprucing up facilities in the kangaroo ward, playroom and playground.
"It was a relationship the foundation would continue to treasure," she said.