Bee Gees legend Robin Gibb is in a coma and his family has gathered by his bedside amid fears he only has days to live ... this according to a new report.

Gibb has been battling colon and liver cancer and is now suffering from pneumonia, says The Sun.

The paper says the 62-year-old's family has gathered for a bedside vigil.

A family friend told the paper, "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."