Geoffrey Keaton and Andrew O'Dwyer died when an ironbark tree, estimated to weigh about three tonnes, fell suddenly on top of their truck as they travelled towards Balmoral, in the Southern Highlands.

Mr Keaton was a 32-year-old deputy captain of his brigade. His mother, Diane, described her son as a "sweet little boy" who changed her life.

"He loved his family, and he spent lots of time growing up with his cousins," she said.

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"He was a mini replica of his dad, and he had a special bond with his brother.

"Geoff wanted to help out all the time, and I'll never forget the time he was keen to help change his brother's nappy until he saw what was in it.

"Geoff projected a tough guy with an attitude image, but we all know he was a big softy, and he was a loyal mate. His mates could talk to him, and he made a real difference.

Mrs Keaton said her son was so excited about becoming a dad and was very proud of his little boy, who, in turn, was a mini replica of his daddy.

Mr Keaton's passion for volunteers was described in a piece of work found in his Year 6 journal, written when he was 11.

His mum read his answer to the inquest. In it, he described why volunteers were so important to everyday life.

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"I'm here to talk about volunteers in our community. Volunteers help without getting paid. Volunteers play a big role in our day to day life," he wrote.

"Volunteer firefighters give up their time. Firefighters work harder in the summer with bushfires all over Australia. Volunteer Firefighters give up their spare time, even during the night.

"Some firefighters give their life in bushfires. Without volunteers, lots of people would miss out.

"There are lots more volunteers that I didn't mention that are just as important and do a good job. So now you know why volunteers are so important."

Following her impact statement, Mrs Keaton said she was proud of her son: "Geoffery, we love you, and we miss your big smiley face every day."

Melissa O'Dwyer, the wife of Andrew O'Dwyer, paid tribute to her late husband.

Ms O'Dwyer described Andrew as "a son, a husband, a brother, a father, an uncle, a friend, a mentor, a photographer and a dedicated RFS volunteer."

"The true character of Andrew was always his ability to capture the best of every element of life and share it with everyone," she said.

"Andrew was hardworking and dedicated much of his life-giving back to the community," she said.

"Andrew was passionate about everything he turned his hand to. He always gave 110 per cent to everything he was involved in.

"He was inclusive and caring and invoked everyone in conversations, games, camping trips and social events.

"His warmth and kind nature were felt by anyone who crossed paths with Andrew."

Ms O'Dwyer said she was proud of the beautiful person that he was and the positive impact he had on so many people.

"As a talented photographer, if he was not behind the camera, he was leading the celebration as the life of the party," she said.

"He was the king of the kids where he helped them explore and empower them with knowledge and a sense of wonder that still lives on in our nephews Xavier and Nixon, in all his friends' children, and most importantly the apple of his eye, his daughter Charlotte.

"He created and captured so many special memories that will live on with us. Andrews's presence and his love for his family were felt by everyone and his great sense of humour made every moment more memorable."

Ms O'Dwyer also shared the heartache that their daughter Charlotte misses her father.

"Andrew longed for years to be a father and when Charlotte was born, he devoted everything to ensuring she was happy, loved and safe," she said.

"He managed to instantly cheekiness stubbornness and adventurous nature into his little girl who misses her hero every day.

"It is truly devastating that Charlotte won't get to know her father in her own special way but I take comfort knowing the best of him lives on in the memories and love for him that we all share.

"And seeing his beautiful nature in her reminds me of the amazing person he was. Andrew was the true definition of a fantastic father to Charlotte."

Ms O'Dwyer said December 19, 2019, was the day they "lost the shining light of the party, the photographer who captured the happiest moments of every element of life, the king of the kids, my best friend and Charlotte's daddy."

"Andrew and I only got to share nine years of what would have been a lifetime together," she said.

"I miss my husband, my partner, my best friend, my future, and my daughter's father. On that day, Charlotte and I lost everything, our shining light."

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