Robin Gibb may be losing his battle against cancer after doctors expressed fears that the singer could be in the final stages of cancer.
The Bee Gees star's family were keeping a bedside vigil, praying for the 62-year-old's survival.
According to the Sun, he appeared to have made a recovery from liver and colon cancer this year, but doctors believe a second tumor may be present. He has also developed pneumonia.
The singer's wife Dwina, brother Barry, 65, daughter Melissa, 37, and sons Spencer, 39, and Robin-John, 29, were at his bedside at a private hospital in Chelsea, West London.
"Our prayers are with Robin. he has kept so positive and always believed he could beat this. Sadly, it looks like he has developed pneumonia, which is very bad in his situation," the Daily Mail quoted a family friend as saying.
"If there is anyone you would put money on pulling through such a dire situation, it would be Robin because he is a fighter. But this is a battle he will struggle to win," the source added.
Gibb revealed his battle with cancer in October 2010. He had emergency surgery to treat a blocked bowel, before a further operation to treat a twisted bowel. Colon cancer was then discovered and it spread to his liver.
His twin brother Maurice died of complications resulting from a twisted intestine in 2003, aged 53.