Bee Gees star Robin Gibb is battling pneumonia and was too ill attend the London premiere of his first classical work, his son revealed Tuesday.
Gibb was slated to attend the Royal Philharmonic's premiere performance of "The Titanic Requiem" and perform a new song, "Don't Cry Alone."
Robin-John Gibb said in a message read out at the concert that his father was in the hospital, but "sends all his love," the BBC reported.
The requiem, a classical composition by Gibb and his son commemorates the April 1912 sinking of the ocean liner and the loss of more than 1,500 lives.
Gibb, 62, underwent intestinal surgery last month.
After being hospitalized late last year for stomach and colon problems, he told the BBC in February that he was making a good recovery. He did not disclose the nature of his illness, but said a growth on his colon had been removed.
Gibb has lost weight and has appeared extremely gaunt in his rare public appearances.
The Bee Gees founding member had a string of hits in the disco era, including "Stayin' Alive."