Barry Gibb found out his brother Robin Gibb had terminal cancer after seeing a photograph of him in the newspaper

In an interview with Radio Times magazine, he recalled: "I saw a picture of Robin in the paper and I took it to my doctor and showed it to him. I said, 'What's wrong with that person?'

"And this doctor is brilliant. He just said, 'Go and see him.' 'Why?' He said, 'Because what I see is cancer.' And I said, 'How do you know that?' He said, 'Pallor of the skin, and his teeth don't look right.' I said, 'What's the prognosis, if you're sure?' He said, 'Three to six months.' That's when I found out."

Although it's been five years since Robin passed away, the 'Stayin' Alive' singer still finds it strange to perform without his bandmate by his side

He said: "On the middle section of 'Nights on Broadway' and 'How Can You Mend a Broken Heart', my throat goes dry. That doesn't mean I'm not going to give it the best shot, but that's when it starts to hit me."

Barry will perform at the Glastonbury festival this weekend and he admits the recent spate of terrorist attacks in the UK - including a bombing at an Ariana Grande concert in Manchester and a van hitting pedestrians before its occupants went on a stabbing rampage in London - has made him concerned about the show.

He said: "After Manchester, I was thinking about Glastonbury. My God, when you gather 100,000 people together, who knows?

"And I don't, and maybe there's nothing to even worry about in any way because I think what we're going to see is security like we've never seen in our lives."