Bee Gees pop star Robin Gibb is in a coma in a London hospital, amid fears he has only days to live, according to reports.
Britain's The Sun newspaper says his family is keeping a bedside vigil for the 62-year-old star, who has been battling colon and liver cancer and now has pneumonia.
It is reported that family and fans of the Bee Gees were last night praying for the star's survival.
On Thursday Gibb's son said the singer would not be able to attend the premiere of their debut classical work, The Titanic Requiem.
Robin-John (RJ) Gibb, who worked on The Titanic Requiem with his father, said his family was hoping for "a speedy recovery".
"He is still in hospital, he's fighting infection and of course - as a lot of people who have family members or friends who endure cancer, they know - there are a lot of periphery problems afterwards they have to deal with," he told BBC Breakfast.
Ongoing health problems forced Gibb to miss the premiere of the Titanic work - to mark the centenary of the ship's ill-fated voyage - at London's Westminster City Hall.
"The one place he really wanted to be in two and and a half years and he couldn't be, and it was heartbreaking, but he'll be able to see it. It was recorded and live streamed," RJ said.
Gibb recently underwent surgery for an ongoing problem with a twisted bowel. The same hereditary intestinal condition led to the death of his twin brother, Maurice, at the age of 53.
Gibb appeared to have made a miracle recovery, but doctors now believe a secondary tumour is present.
Gibb's wife, Dwina, brother Barry, 65, daughter Melissa, 37, and sons Spencer, 39, and RJ, 29, were at his bedside in a private hospital in Chelsea in west London, according to The Sun.
Gibb's health problems began last October when he had emergency surgery to treat a blocked bowel.
Last month Gibb told The Sun: "I sometimes wonder if all the tragedies my family has suffered - like Andy and Maurice dying so young and everything that's happened to me recently - is a kind of karmic price we are paying for all the fame and fortune we've had."
Gibb also praised his wife, who has helped him fight his cancer fight.
"She gave me health foods and brewed herb teas for me, alongside conventional treatment," he said.