Labor frontbencher Penny Wong is used to hearing arguments against same-sex marriage.
But for Australia's most prominent gay politician - one hurts more than others.
"The 'think of the children' argument is among the most hurtful in the marriage equality debate," Senator Wong has written in an essay in The Monthly magazine.
"It posits that gay and lesbian relationships harm children, that gay and lesbian parents are bad parents."
Senator Wong, who has two young daughters with her partner Sophie Allouache, added that the "most bigoted expression" of this argument - via conservative Christians - is that the children of same-sex parents are another "stolen generation".
"This is not an argument against marriage equality. It is an argument against gay and lesbian Australians being parents. Actually, it is an argument about gay and lesbian Australians being at all," Labor's trade spokeswoman wrote.
Senator Wong's comments come as Parliament returns for 2016 with debate about same-sex marriage continuing to rage. While the Turnbull government works on the wording and process for a plebiscite on the issue, Labor is again pushing for Parliament to resolve the issue with a vote.
According to Australian Marriage Equality - which has been monitoring the numbers in Canberra - provided Liberal MPs had a free vote, there is now slim majority of support in both houses for same-sex marriage.
On Sunday, Labor leader Bill Shorten told reporters, "marriage equality should just happen" without going through the plebiscite process.
Senator Wong's essay, written over the Christmas holidays, also talks about how she sees society shifting on the issue as she goes about her everyday life.
"I can sense change ... in the thoughtful messages my partner, Sophie, and I received on the birth of our daughters; in the kindness of strangers stopping me in the street to ask after our family; in the attitudes of a man in work gear, extending a calloused hand, telling me how wonderful it is to be a parent, and a woman in the market handing our four-year old another biscotti ..."
Senate Wong says these acts are not political, "they're human".
"Most people recognise what your marriage laws don't: gay and lesbian Australians are just like everybody else."
On Monday, Finance Minister Mathias Cormann strongly backed the Coalition's plans to hold a plebiscite - costing an estimated $160 million - after the next federal election.
"The truth is, the Coalition party room has determined a course of action. I fully support that course of action," he told Radio National.
Senator Cormann said he supported the "current definition of marriage". But said "obviously" if Australia voted "yes" then the Parliament would have to act in support of the reform.
In 2012, Senator Wong was hailed by marriage equality advocates and set social media alight for comments on the ABC's Q&A when she shot down then shadow treasurer Joe Hockey.
Mr Hockey argued against same-sex marriage because children should have a mother and father.
In response, Wong said: "When you say those things, Joe, what you're saying to not just me but people like me is that the most important thing in our lives, which is the people we love, is somehow less good, less valued ... I know what my family is worth."