Labor backbencher Linda Burney has taken leave from Parliament to deal with the sudden death of her 33-year-old son.
Ms Burney has released a statement saying her son had struggled with mental illness and addiction and that while the cause of his death was unknown, it did not appear to be suspicious.
She said it was a "dire, grief-stricken time".
"Binni is 33 years old. He is a caring and loving man," she said.
"He has struggled with mental health and with addiction. He tried so hard to conquer his demons, as I and my family have tried so hard to support him in every way we could.
"I don't want to pre-empt subsequent inquiry, but we all thought we were getting somewhere.
"I don't know what life will be like without him."
Politicians from all sides offer condolences
Question Time began with condolences for Ms Burney and her family.
Prime Minister Malcolm Turnbull said the loss of a child was the "worst dread" for any parent.
"Linda's loss is unspeakably sad. She is not with us today, she has leave, but we are with her. We are all with her in love and in heartfelt sympathy," he said.
"She is cast deep in grief, but she does not grieve alone. She is a strong woman. Stronger because of the love that all of us, the sympathy that all of us, the friendship that all of us share with her at this tragic time, for her and for her family."
Ms Burney's party leader, Bill Shorten, offered his deepest condolences to Ms Burney's family.
"This is just so sad. As Jenny Macklin and I were speaking to her last night, the grief is terrible. Losing a child is every parent's nightmare," he said.
"It is, as Shakespeare once said, the grief that fills up the room. We know how much Linda loved her son, and we know how much her son loved Linda.
"In this time of deep sadness, can I please request that the media respect her family's privacy, and I know that they will."
Mr Shorten added that Ms Burney's family had asked people to contribute to the Glen Centre, a drug and alcohol rehabilitation unit on the NSW Central Coast.
"We send our love and solidarity to our friend and colleague and her family at this time," he added.
