In 1968, Gibb married Molly Hullis, a secretary in Robert Stigwood's organisation.
They had two children together, Spencer (b. 1972) and Melissa (b. 1974).
The couple divorced in 1980 after years of living separate lives, with Gibb almost permanently in the US and Hullis remaining in the UK; she filed for divorce on 22 May 1980.
On 9 September 1983, Gibb was arrested and sentenced to 14 days in jail for speaking to the press about his previous marriage in breach of a court order.

Gibb's second marriage, from 1985 until his death, was to Dwina Murphy, an author and artist.
She is interested in the Druidry religion and is a follower of the neo-Hindu Brahma Kumaris movement.
The couple had a son, Robin-John (known as RJ, b. 1983).
Robin-John's first major musical project is the Titanic Requiem (2012), written with Gibb and first performed at the Central Hall, Westminster, London, on 10 April 2012, by the Royal Philharmonic Orchestra and RSVP Voices.

At 50 years of age, Gibb began an affair with his 25-year-old housekeeper, Claire Yang, that eight years later produced his fourth child, Snow Evelyn Robin Juliet Gibb, born 4 November 2008.

Gibb and his wife divided their time between their homes in Peel, Isle of Man, their mansion in Miami, Florida and their main residence in Thame, Oxfordshire.

On 10 March 1988, younger brother Andy died in Oxford, of myocarditis.
On 12 January 2003, twin brother Maurice died in Miami Beach, Florida, of complications from a twisted intestine.

Politically, Gibb was a supporter of New Labour, the British Labour Party when Tony Blair was Prime Minister.
He launched a rally in Huddersfield, West Yorkshire, ahead of the 2005 General Election.
He was a close friend of Blair, who was criticised for staying at Gibb's Miami mansion during Christmas 2006.
In 2008, Gibb publicly stated that he continued to get on "like a house on fire" with Blair and said that the then Labour prime minister, Gordon Brown, regularly listened to the Bee Gees. "
He listens to our music every day.
Gordon likes our music and I like Gordon", he told The Times.
In a tribute upon his death, longtime friend Tony Blair said: "Robin was not only an exceptional and extraordinary musician and songwriter, he was a highly intelligent, interesting and committed human being.
He was a great friend with a wonderful open and fertile mind and a student of history and politics."

Gibb worked on behalf of several charities.
He was the organiser of the Sunseeker Ball in aid of the Outward Bound Trust.
For the International Confederation of Societies of Authors and Composers (CISAC), Gibb served as president from 2007 to 2012.
He was also the longest serving president (2008–2011) of the Heritage Foundation, which honours figures of British culture and facilitated his campaign on behalf of the Bomber Command Memorial Appeal.
In 1968, Gibb married Molly Hullis, a secretary in Robert Stigwood's organisation. They had two children together, Spencer (b. 1972) and Melissa (b. 1974). The couple divorced in 1980 after years of living separate lives, with Gibb almost permanently in the US and Hullis remaining in the UK; she filed for divorce on 22 May 1980. On 9 September 1983, Gibb was arrested and sentenced to 14 days in jail for speaking to the press about his previous marriage in breach of a court order.
Gibb's second marriage, from 1985 until his death, was to Dwina Murphy, an author and artist. She is interested in the Druidry religion and is a follower of the neo-Hindu Brahma Kumaris movement. The couple had a son, Robin-John (known as RJ, b. 1983). Robin-John's first major musical project is the Titanic Requiem (2012), written with Gibb and first performed at the Central Hall, Westminster, London, on 10 April 2012, by the Royal Philharmonic Orchestra and RSVP Voices.
At 50 years of age, Gibb began an affair with his 25-year-old housekeeper, Claire Yang, that eight years later produced his fourth child, Snow Evelyn Robin Juliet Gibb, born 4 November 2008.
Gibb and his wife divided their time between their homes in Peel, Isle of Man, their mansion in Miami, Florida and their main residence in Thame, Oxfordshire.
On 10 March 1988, younger brother Andy died in Oxford, of myocarditis. On 12 January 2003, twin brother Maurice died in Miami Beach, Florida, of complications from a twisted intestine.
Politically, Gibb was a supporter of New Labour, the British Labour Party when Tony Blair was Prime Minister. He launched a rally in Huddersfield, West Yorkshire, ahead of the 2005 General Election. He was a close friend of Blair, who was criticised for staying at Gibb's Miami mansion during Christmas 2006. In 2008, Gibb publicly stated that he continued to get on "like a house on fire" with Blair and said that the then Labour prime minister, Gordon Brown, regularly listened to the Bee Gees. "He listens to our music every day. Gordon likes our music and I like Gordon", he told The Times. In a tribute upon his death, longtime friend Tony Blair said: "Robin was not only an exceptional and extraordinary musician and songwriter, he was a highly intelligent, interesting and committed human being. He was a great friend with a wonderful open and fertile mind and a student of history and politics."
Gibb worked on behalf of several charities. He was the organiser of the Sunseeker Ball in aid of the Outward Bound Trust. For the International Confederation of Societies of Authors and Composers (CISAC), Gibb served as president from 2007 to 2012. He was also the longest serving president (2008–2011) of the Heritage Foundation, which honours figures of British culture and facilitated his campaign on behalf of the Bomber Command Memorial Appeal.
Robin Gibb