27/07/2016 10:03 AM AEST | Updated 27/07/2016 10:36 AM AEST

Father Of Stuart And Thomas Kelly Posts Heartbreaking Message After Stuart's Death

Stuart Kelly was found dead at his Sydney home.

Ralph Kelly, with his sons Thomas (L) and Stuart.

A parent should never have to bury their own child. Sydney father Ralph Kelly, is preparing to bury his second.

The father of one-punch victim Thomas Kelly, who died after a sucker punch in Kings Cross in 2012, posted a heartbreaking Facebook message on Tuesday after it was announced his younger son Stuart had died.

Stuart, who was 14 when his older brother died, was found dead at home in Sydney's northern beaches. Police are not treating his death as suspicious.

"The most painful goodbyes are the ones that are never said and never explained", Ralph wrote on Facebook.

Ralph Kelly and his wife Kathy established the Kelly Foundation after the death of their eldest son nearly four years ago, triggering a significant campaign against alcohol-fuelled violence.

They also established the Thomas Kelly Youth Foundation and the Take Kare Safe Spaces program, building a legacy for their son as they campaigned for a better understanding of alcohol consumption, public safety and the shocking effect that one single punch can have.

Stuart Kelly's alma mater, The King's School, have expressed their profound sadness at the passing of their former student.

Tim Hawkes, the school's headmaster, issued this statement on Tuesday.

"To have lost two sons in such circumstances is beyond awful.

The school has already been in contact with the Kelly family and will be offering them all the support we can.

As a student, Stuart was greatly respected. He was a school prefect who possessed a quiet integrity that made him enormously effective as a leader.

The strength and character shown by Stuart when his brother was killed by a one-punch attack in July 2012 was extraordinary. Stuart has since gone on to support the work of the Kelly Foundation and to campaign against alcohol-fuelled violence."

Stuart Kelly was "too young" to speak publicly after his brother was felled by Kieren Loveridge nearly four years ago. Last year he delivered a stirring address which revealed the profound impact of his brother's death.

Stuart Kelly was just 14 when his brother, Thomas, died.

"I carry a deep scar that you cannot see. It's always there, never leaves. It's just below the surface of your skin, and surfaces when you least expect it.

Tom never deserved to die that night, it was not meant to be his time. In fact, I believe now that it could and should have been avoided. Our family lost a son and a brother. I ask all of you to look at me, I am but one person who has been affected by violence.

It is a sentence that I have to carry for the rest of my life. My mother, father and sister now carry this sentence. Our relatives and friends, Tom's friends, carry this sentence.

We are not alone, there are many many thousands of other who are directly affected by senseless violence every year. Premier (Mike Baird) will you make this promise tonight?

Australia is an alcoholic. We need to rethink the way we drink."

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