A volunteer firefighter killed during the NSW bushfire crisis has been farewelled in an emotional funeral procession involving his fiancee and young son.

Geoffrey Keaton, 32, died on December 19 when his fire truck rolled while battling the large Green Wattle Creek blaze near the town of Buxton, south-west of Sydney.

Mr Keaton was remembered at a funeral at Pinegrove Memorial Park in Minchinbury, in western Sydney, on Thursday morning.

Geoffrey Keaton (left) and Andrew O’Dwyer died fighting a fire south-west of Sydney in December.

Mr Keaton’s fiancee Jess Hayes and 19-month-old son Harvey were part of a long procession of fire trucks that drove to the service to pay tribute to the dead volunteer firefighter.

An NSW Rural Fire Service guard of honour was also formed.

RFS Commissioner Shane Fitzsimmons presented Harvey with Mr Keaton’s posthumously awarded Commissioner’s Commendation for Bravery and Service at the service.

The #NSWRFS farewelled one of our own today, Geoffrey Keaton, one of two firefighters who lost their lives fighting fires on 19 December 2019. @RFSCommissioner Fitzsimmons honored Geoffrey today by posthumously awarding him Commissioner’s Commendations for Bravery and Service. pic.twitter.com/VFeZMxNuJq

— NSW RFS (@NSWRFS) January 2, 2020

Mr Keaton was part of the 68-strong Horsley Park Rural Fire Brigade.

“An additional public memorial service is also currently being planned by NSW RFS in the coming weeks,” the brigade said.

Prime Minister Scott Morrison and wife Jenny were among those at the service to pay tribute to Mr Keaton.

“It was important to be able to honour his great sacrifice and his tremendous service,” Mr Morrison said after the funeral.

“Sadly, we will be attending two more of these services in the not-too-distant future.

Volunteer Andrew O’Dwyer, 36, was also killed in the crash. He will be remembered at a separate service next week.

-with AAP