TO the haunting words of Charlie Puth and Wiz Khalifa's song See You Again, family, friends, veterans and serving members of the Australian Defence Force farewelled Brisbane Private Liam Wolf today.

In steady rain about 400 mourners, including more than 100 military personnel, gathered at St Mary Mackillop Church in Birkdale, where Rev Frank Jones conducted the emotional service for the Alexandra Hills 18-year-old who had dreamt of being a commando.

He was just days away from completing his army training when police suspect he fell 5m from an underground ladder at Kapooka, in NSW, last month.

Liam's siblings and friends remembered a young man - sometimes a larrikin - who lived with the dream of becoming an elite commando.

After an hour, they left the church to the words "it's been a long day without you my friend and I'll tell you all about it when I see you again".

The rain had stopped but the tears flowed as the hearse carrying Liam's body left the church en route to the private burial

The Department of Defence, on behalf of Liam's family, thanked "everyone for their messages, support and kindness" over his loss.

"Our beloved son and brother, Private Liam Wolf, was completing basic training at the Army Recruit Training Centre at Kapooka in New South Wales when he was involved in a training incident," the statement said.

"Tragically, Liam passed away as a result of his injuries.

"Our deep gratitude and thanks goes out to the staff and recruits at the Army Recruit Training Centre who provided Liam with initial medical assistance, and the staff at Kapooka Health Centre, Wagga Wagga Base Hospital and St George Hospital Intensive Care Unit for their professionalism and care."

Veteran and Redland City Councillor Paul Golle, who attended the service, said it was "absolutely heartbreaking".

"The loss has resonated across the defence community and my heartfelt and deepest condolences go out to Liam's family and friends," Cr Golle said.

"Today's service with the defence force members and veterans present, shows that the defence force is not just a job, it's a family. Liam was our brother and he will be remembered.

"Liam was a Digger. He valued life to the end."