Nelson Mandela's daughter Zindzi revealed her father is "fine" but "frail" as a film about his life had its royal premiere in London.
She joined the Duke and Duchess of Cambridge and the film's stars Idris Elba, Naomie Harris and Tony Kgoroge on the red carpet at Leicester Square for the UK premiere of Mandela: Long Walk To Freedom.
"My father is fine. He's 95 years old and he is pretty frail. We are hoping to see more of him," she said of the former South African leader, who is in ill health.
She revealed Mr Mandela has seen some clips of the film, which is adapted from his autobiography of the same name and stars Elba as the former South African president.
"I love it. I think it's authentic," she said.
William and Kate reached the red carpet a little over an hour after the stars and guests arrived.
The Duchess, wearing a figure-hugging cream dress by French designer Roland Mouret, was the main focus for the cameras.
Once inside, the royal couple met Cinema and Television Benelovent Fund trustees, beneficiaries, Mr Mandela's daughter and members of the film's cast and crew.
The Royal Film Performance is held annually and is the principal fundraising event for the CTBF, the trade charity for the UK film and television industries.
The fund provides care and financial support to industry employees and their families who suffer hardship due to bereavement, illness, redundancy or other misfortunes.
CTBF president Barry Jenkins said the fund was thrilled to be able to host the royal premiere of the joint South African-British production, which was a sell-out.
" We are most grateful to the Royal Family for their continued support since the very first Royal Film Performance event back in 1946," he said.
"The funds raised from this event make a huge difference to the lives of industry colleagues and their families in times of great need."
The film will be released in cinemas across the UK and Ireland on January 3.
Luther star Elba was joined on the red carpet by his mother.
"It's a very special night for an important film. I am looking forward to meeting them (the Duke and Duchess of Cambridge)," said the 41-year-old.
"The Royal Family have had a long history with Mandela so it's a real honour that they have come out to support this film. This is an independent film and for them to come out and see this film is a really big deal," he added.
Elba, who is also known for playing Stringer Bell in US series The Wire, joked that he would try to get William to belt out a tune at the film's after party following his impromptu sing-along with Jon Bon Jovi and Taylor Swift at the Winter Whites charity gala.
"I heard he likes to sing a bit so I've got some old revival tunes so we'll see if he gets into that," he said.
His co-star Harris, who braved the cold in a strapless black gown by Alexander McQueen, spoke of her excitement over meeting Kate.
"I've met Wills a few times now - he's lovely. Absolutely charming and down-to-earth so I'm excited to meet Kate for the first time," said the Skyfall actress.
Justin Chadwick's big-screen adaptation of Mandela's autobiography of the same name, produced by Anant Singh, follows the leader's life from his childhood, his years imprisoned on Robben Island through to his inauguration as the first democratically elected President of South Africa in 1994.
"I think he means freedom and forgiveness. I think Mandela's legacy for me is forgiveness," Elba said.
Harris added: "He is an incredible individual who, despite having 27 years of his life taken away, still has compassion, understanding and forgiveness when he came out of prison. That's just extraordinary.
"It is healing for South Africa and the world as well."
Mandela: Long Walk To Freedom opens in cinemas on January 3.
CTBF trustee Derek Cooper said meeting Kate was exciting, given last year she was unable to attend the royal premiere as she was in hospital with morning sickness while pregnant with Prince George.
"We met His Royal Highness, but we couldn't meet her because she was sick, so it was brilliant, exciting news when we heard she was coming this year," he said.
Hilda Prewett, a 101-year-old beneficiary of the fund, said she was thrilled to meet the duchess and had an interesting bit of history to share with her.
"It was wonderful to meet her, very exciting for me," she said.
"Kate lived at Bucklebury and my daughter married the son that lived next door to her."
Ms Prewett said her son works in the industry and the fund helps pay for her care at Glebelands Nursing Home.