She is no “shrinking violet”, but Senator Penny Wong’s voice still wavered slightly in the midst of a blistering speech against the gay marriage plebiscite on Wednesday.

“I know what a hard debate’s like,” Labor’s leader in the Senate said.

“But I tell you, have a read about some of the things that are said about us and our families, and then come back and tell us that this is a unifying moment.”

Senator Wong, who has two children with her female partner, was responding to Finance Minister Mathias Cormann’s claim that the plebiscite could be a “unifying” moment for the nation.

Mathias Cormann said he held Penny Wong in high regard. Photo: AAP

“I’m not a bigot or a bad person because I happen to think the definition of marriage should be a particular way,” Senator Cormann had said.

“Those that don’t participate in this debate in a way respectful way, that is regrettable. I think the Australian community is able to deal with this and to handle this.”

In a forceful defence of Australia’s gay couples and their children, including her own, Senator Wong begged to differ.

“The Australian Christian Lobby described our children as the Stolen Generation,” she told him.

“We love our children. And I object to, as do (sic) every person who cares about children, and as do all those … same-sex couples who have kids, to being told our children are a Stolen Generation.”

Watch Penny Wong’s speech

“You talk about unifying moments. It’s not a unifying moment. It’s exposing our children to that kind of hatred.

“And I wouldn’t mind so much if you were prepared to speak out on it. If the Prime Minister were prepared to stand up and say, ‘That is wrong.’

“But what does he do? ‘Oh, it’s a dreadful reason to not trust the Australian people. Don’t be silly, of course we can have a sensible debate’.

“Well maybe he should stand up for people who don’t have a voice. Because we know the sort of debate that is already there. And let me say, for many children in same-sex couple-parented families, and for many young LGBTI kids, this ain’t a respectful debate already.”

Senator Cormann responded to the speech later on Wednesday morning, telling Sky News: “I have a very high regard for Penny Wong.”

“I agree with her. It’s going to be very important to conduct this debate with courtesy and respect.”

The speech came as same-sex marriage advocates announced they would file a injunction to stop the postal plebiscite, amid lingering doubts about the ABS’s role in the process.

Asked about the potential cost of such a bid, same-sex marriage advocate Rodney Croome said: “It doesn’t matter how much it costs. Whatever the cost of mounting a High Court challenge, it doesn’t compare to the human cost of conducting this postal vote.”

The government will push ahead with the postal vote option after the Senate killed off its preferred method – a compulsory attendance vote – on Wednesday morning.

Former prime minister Tony Abbott emerged on Wednesday as a leading figure on the ‘no’ side on the first unofficial day of campaigning.

“Obviously I will be voting no, but in the end this is not about the politicians, this is about the people, it’s about your view,” Mr Abbott said.

“And I say to you if you don’t like same-sex marriage, vote ‘No’,” he said.

“If you’re worried about religious freedom and freedom of speech, vote ‘No’, and if you don’t like political correctness, vote ‘No’ because voting ‘No’ will help to stop political correctness in its tracks.”

Mr Abbott was quickly rebuked by his sister, openly gay Liberal councillor Christine Forster, who said: “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.”