ROSS Thompson has been through hell.
But all he wants to do is help prevent more lives being damaged in the way his was.
In 2005, his son Michael was brutally murdered in a triple homicide in Toowoomba.
Three months later, his second son, John was killed in a car accident.
Mr Thompson tells his story candidly, and he tells it again and again, to school kids, to teachers, to prisoners in jails.
He says talking about it - "that's my therapy".
The anti-violence advocate worked for six years as general manager of the Queensland Homicide Victims' Support Group, but now retired, he is still working hard to spread his message.
"Probably until I'm six feet under I'm going to be preaching," he said.
On Saturday he visited a Rotary youth camp in Tannum Sands to talk to 44 teenagers about violence.
His own son was killed by juvenile offenders.
"It doesn't take much to kill someone."
Mr Thompson says, "if you hit someone and they go down badly, they can die".
He told the students, "it's about making a choice not to be violent."
He talked openly about his upbringing with a violent father.
One time, when his father had assaulted his mother, Mr Thompson hit his father.
He said once he'd done it, "I decided never to hit anyone again".
The room was silent for the duration of Mr Thompson's talk.
One of the Rotary camp hosts, Sue Gammon, said "the kids have taken it on board. (The fact that it's his life) brings it home to the kids. They'll remember this."
"It's really quite confronting," she said, "especially because Ross shares such a personal story and it's not just one tragedy, it's two tragedies.
"How can one person cope with all this?
"And he's taken it and he's gone out and he's tried to change other people's lives."
While Mr Thompson seeks to prevent violence by talking to children about the consequences, both for their victims and for themselves, he is also an advocate for tougher sentences for violent juvenile offenders.
"If I just save one life, just one, it's all worth it, because life is priceless," he said.
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