Linda Burney's tearful tribute to son in Parliament, six weeks after his death.

Linda Burney has offered a tear-filled tribute to her late son Binni during a powerful speech on same-sex marriage.

The Labor frontbencher rose in federal parliament on Tuesday to explain her longstanding support for marriage equality.

“I have never had a second thought. It seemed so obvious to me,” she told colleagues.

Ms Burney lost her 33-year-old son Binni Kirkbright-Burney, who was gay, six weeks ago.

He was found dead in their Sydney home. Police declared there were no suspicious circumstances.

“I support marriage equality as someone who has, and has had, loved ones who identify as LGBTIQ,” Ms Burney told parliament through tears.

“To them, marriage equality would mean so much. I honour these people and, in particular, my late son Binni.”

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Ms Burney said she had seen firsthand the confusion, anxiety and pain many young people experienced in dealing with their sexuality.

Australia’s first female Aboriginal MP, Ms Burney said she also supported marriage equality “as someone who is a member of a community that has experienced great discrimination and injustice.”

She knew all too well “what it means to be rejected, understands what intergenerational trauma feels like, and what hurt and distress does to you.”

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