And the group has called on the medical community to debunk "damaging misrepresentations" of the evidence being used by the "no" campaign in the postal vote on same-sex marriage, saying the real public health risk comes from discrimination.

The 13 specialists, who include Professor Frank Oberklaid from the Murdoch Children's Research Institute, and Associate Professor Michelle Telfer, from the Royal Children's Hospital in Melbourne, write in the Medical Journal of Australia: "The research tells us that children and adolescents with same-sex parents are doing well, despite the discrimination their families endure. This will not continue for long in the face of hostile debate.

"When damaging misrepresentations of the evidence circulate unchecked, the potential for stigmatising rhetoric to generate greater harm to this community increases."

Public statements should be based on accurate, objective interpretations of the best available evidence, and the correction of inaccurate information, the group says.

Its review looks at at least three international, and one Australian, studies that have analysed the findings of dozens of pieces of research on the wellbeing of same-sex families.

The consensus internationally is that children with same-sex parents do just as well as children raised by heterosexual couples.

And it's the family "processes" - the quality of parenting, parental wellbeing and the quality of relationships - rather than a family's structure that makes a meaningful difference to children's wellbeing, the research shows.

At a marriage equality rally in Melbourne on Sunday, nine-year-old Alex Bradshaw-Allen took to the stage alongside her mothers: Ro Allen, the Victorian Commissioner for Gender and Sexuality, and Kaye Bradshaw.

With a cheeky grin on her face, Alex told the crowd they could call her "Commish jnr".

"I love my family, no matter what the postal plebiscite says," Alex told the rally of about 500 people. "I love my family and they love me, no matter what."

There are studies that have concluded children of same-sex families actually do better than other children, showing better psychological adjustment and open-mindedness. But the group of experts notes these might reflect the high-quality parenting and economic status of the families studied.

Studies that concluded children with same-sex families did poorly have been widely criticised for the limitations in their methodology, the review found.

Young LGBTIQ people experience some of the highest rates of psychological distress of any group in Australia. This is largely attributed to the harassment, stigma and discrimination they regularly endure.

Recent research in the US found that legalising same-sex marriage has a positive effect on the mental health of LGBTI young people.

The authors of the article in the Medical Journal of Australia, a publication of the Australian Medical Association, urged readers to add their voices to the public debate, saying inaction was not an option when harm was the likely result.

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