David Trimble has 'taken journey' on same-sex marriage
David Trimble put his head in his hands when his daughter came out to him but she said he has since "taken that journey" over same-sex marriage.
Vicky Trimble told BBC Talkback her father changed his views on the issue after she told her parents she is gay.
Ms Trimble said she met photographer Rosalind Stephens in London in 2013, falling in love at first sight.
They married in 2017 in Scotland with Lord Trimble giving his daughter away.
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Lord Trimble is a former Northern Ireland first minister and a former leader of the Ulster Unionist Party (UUP), who won the Nobel Peace Prize in 1998 for his role in the Good Friday Agreement, the key document that helped bring the Troubles in Northern Ireland to an end.
He has opposed same-sex marriage in the past but told the House of Lords his daughter's marriage had changed his view.
Ms Trimble, now 35, told her parents she was a lesbian when she was in her late 20s, shortly before the UK voted in favour of same-sex marriage and in the knowledge her father would vote against it.
"My dad's reaction was to put his head in his hands," she told BBC Talkback, but said her mother did not seem surprised.
She said Lord Trimble's view of same-sex marriage subsequently changed.
"He has taken that journey where he has realised that I should have the same rights as the rest of his children," she said.
Ms Trimble said it is upsetting same-sex marriages are not recognised in Northern Ireland but she is hopeful that will soon change, even if the assembly and devolution are restored.
Same-sex marriage is one of the issues that has divided the two largest parties, Sinn Féin and the DUP, preventing an executive being formed after it collapsed in 2017.
'Acquiesced to it'
The former Ulster Unionist leader surprised some when he revealed his daughter had married her girlfriend during the debate in the Lords on Wednesday.
"I have found myself taking a particular position with regard to same-sex marriage, which was forced upon me when my elder daughter got married to her girlfriend," he said.
"I cannot change that, and I cannot now go around saying that I am opposed to it because I acquiesced to it. There we are."
Ms Trimble said she was "a little surprised" by that wording.
"For him it was either lose a daughter or come to terms with realising that a gay relationship is just like any other.
"There is a part of me that wonders if it was a slightly missed opportunity to show there is a level of acceptance and tolerance within unionism in Northern Ireland."
However she said that how Lord Trimble deals with her and her wife speaks louder than his words.
Lord Trimble had voted against the Civil Partnerships Bill in 2004 and, in previous years, the Ulster Unionist Party (UUP) was opposed to same-sex marriage.
Timeline of same-sex marriage
- England and Wales legalised same-sex marriage in July 2013, with the change coming into force in March 2014
- Scotland legislated for same-sex marriage in February 2014 and it came into effect in December that year
- The Republic of Ireland legalised same-sex marriage in a referendum in May 2015, becoming the only country in the world to do so by popular vote
- Ireland's first same-sex marriage took place in November 2015
Who is Lord Trimble?
David Trimble entered politics through the hardline Vanguard Party in the early 1970s. He joined mainstream unionism in 1978 and entered Westminster as the MP for Upper Bann in 1990.
His decision in 1998 to sign the Good Friday Agreement, as leader of the Ulster Unionist Party (UUP) won him support in London, Dublin and Washington and led to him sharing the Nobel Peace Prize with SDLP leader John Hume.
He stepped down as leader of the UUP, after losing his Westminster seat in Upper Bann in the 2005 general election.
He was made a life peer in 2006, later joining the Conservatives.