Robin Gibb's son is glad he agreed to help his father create music to mark the 100th anniversary of the sinking of the Titanic, because the project brought them "closer together" after the singer's cancer diagnosis.

The Bee Gees star is currently battling colon cancer, which has spread to his liver, but he refused to let the disease halt work on a requiem to mark 100 years since the 1912 ocean tragedy.

Gibb collaborated on the project with his son R.J., who reveals he first began to fear for the star's health in 2009, when he started to lose weight and feel tired, and he feared the music would be his father's final work.

He tells Britain's Sunday Express, "We started noticing that he was feeling more and more tired and getting a bit skinny. Then he was diagnosed. At first my father wouldn't talk about it but as he went through chemotherapy and realized it wasn't as bad as he feared he opened up to us. You don't want to think about it but I knew that Titanic could end up being our final project together."

R.J. "savoured" every moment of working with the singer and admits the project brought them closer together.

He adds, "We have always been close but this has brought us really close together. I savoured every moment but there was never a sense of urgency or fear because of the disease, to get it done quick; we just threw ourselves into the work.

"We had fun. It was a labour of love. The project helped me deal with his disease too. Now that the truth is out people congratulate him for overcoming it. They are not looking at him like a sick man." (c) WENN