Fathers and daughters are hardly strangers to disagreement. And so it is with Tony Abbott, the prominent Australian anti-same-sex marriage campaigner, and his daughter Frances, who has backed the rival yes campaign in the country’s keenly contested postal survey.

Two weeks after she put herself at odds with her father, the country’s former prime minister, with a post on Instagram, Frances Abbott has appeared in an advert calling on Australians to back marriage equality in the country’s non-binding, voluntary survey.

“You can’t help who you fall in love with. Love just happens sometimes and it’s unexpected and that’s kind of what’s the awesome thing about it,” Frances Abbott said in the video released by the Equality Campaign.

She referred to her aunt – and Tony Abbott’s sister – Christine Forster, who lives with her partner, Virginia Edwards. “I don’t think she planned to fall in love with Virginia – it just happened. It never really changed anything, she was still aunty Chris – she’s still going to be at Christmas, she’s still going to be at the family barbecues, her children are still my cousins,” Frances Abbott said.



“This is why it really just doesn’t make sense to me that [gay marriage] is not allowed.”

The campaign over the issue has been bruising – not least to Tony Abbott, who was allegedly headbutted in the face by a yes campaigner last week.

Astro Labe, 38, has been arrested and charged after the incident. While he has since said it was not related to the campaign, it has been claimed he was wearing a vote yes badge. “It was just a reminder of how ugly this debate is getting,” Abbott told an Australian radio station.

His daughter believes a yes vote would be a force for good. “I think marriage equality would make society a much better place, with less fear of discrimination or fear of isolation or loneliness,” she said in the video.

The law “has to change and it will change”, she added.

Referring to her father’s prominence in the national debate, Frances Abbott said: “I think it’s well known that, within my family, we have people that sit on the other side of the fence. My mother and my father raised me to stand up for what I believe in.

“I posted that picture on Instagram to show this is what I think is right. In my post, I said I’m not interested in politics. But this is more than politics. What this comes down to is love.”

Frances Abbott’s Instagram post from 14 September

Tony Abbott has also clashed with his sister over the issue in a back-and-forth on Twitter. “If you don’t like same-sex marriage: vote no,” and “if you are worried about freedom of speech and freedom of religion, vote no,” he wrote.

She hit back: “If you value mutual respect: vote yes. If you want all Australians to be equal: vote yes. If you believe in free speech: vote yes.”

Polls have put the yes vote ahead, though support had slowed recently. The Guardian Essential poll, published on Monday, found that 58% of Australians supported the proposed change in the law. That was up three points from last week, compared with 33% who oppose it and 9% who are undecided.

More than a third have already cast their votes, with 45% saying they will still vote and 8% saying they probably will. Among those who have already voted, 72% supported yes and only 26% supported no.

People leaning towards yes who had not yet voted also appeared more likely to turn out than their no-supporting counterparts.

The deadline for votes to be received by the Australian Bureau of Statistics is 7 November and the results will be announced on 15 November. If a majority show support, the Australian parliament will debate and vote on the issue.