Gibb, a former member of the Bee Gees pop group, and his son, Robin-John, composed a classical piece called the "Titanic Requiem," which was performed by the Royal Philharmonic Orchestra at Westminster Central Hall to mark this weekend's 100th anniversary of the sinking of the famous ocean liner on its maiden voyage.
Father and son were to attend Tuesday's show and the elder Gibb, 62, also was scheduled to sing his new song, "Don't Cry Alone," the BBC said.
His hospitalization was announced at the beginning of the concert and a message read aloud from his son said Robin Gibb "sends all his love," the BBC reported.
"We are all praying for him and hoping he has a speedy recovery," the message from R.J. Gibb said.
Robin Gibb has been battling cancer and recently underwent intestinal surgery.
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