Robin Gibb has moved his eyes and "attempted to speak".
The Bee Gees star is battling cancer and has developed pneumonia, causing him to fall into a coma. His loved ones have rallied around him in hospital and it now seems that he is improving.
"There were flickers of life from Robin. His eyes moved and there was an attempt at speech," a source told British newspaper The Sun. "It was a good sign he is fighting hard for his life but he is certainly not out of the woods yet. The family have to remain very cautious."
Robin's family have been playing him music in a bid to help wake him up. His brother Barry, who was also in The Bee Gees, has been singing to him in hospital.
Robin's wife Dwina and his children have spent most of the last week by his side at the medical centre in Chelsea, London, where he is being cared for.
The singer has been battling colon and liver cancer, after he was diagnosed last year. It was thought that he had beaten the disease, although his health then took a turn for the worse.
Dwina has been a constant source of support for the 62-year-old and has been insisting to friends that the star is strong enough to pull through his current problems.
"Dwina has been incredible. She has been such a rock of support for everyone and is just so, so strong, remains upbeat and is just willing Robin on and on," a source recently told British newspaper The Mirror. "She will never give up – just like Robin's attitude throughout all his recent health problems. The pair share that same fighting mentality."