Spurred on by his parents who published his books for him, first stapled together, and then as they got larger, sewn together on the sewing machine, this is Arlo's first professionally published novel.
While support from his parents was great, it was encouragement from his teachers too, which also played a large role in inspiring his love of writing.
"His Year 6 teacher Steve Aiken would start each day off by asking the students to write for half an hour or so," Arlo's mother Vida Kelly said.
Encouraging them to find a comfy spot anywhere in the classroom, they could write about whatever they wanted with only 'Mr A', themselves, and whoever they wanted seeing it.
"Nothing was marked, it was purely for themselves, and it had such a positive impact on students in so many ways.
"I think this helped cement Arlo's passion for storytelling."
Echo is about Eric, a young visually-impaired boy fighting for independence from his parents as he grows up.
Set on the east coast of New Zealand, the book is inspired by Arlo's summer holidays at Makorori Beach.
"My holidays in Makorori Beach where my dad grew up are some of the best times of my life," Arlo said.
"It is a beautiful area with a sweeping beach, and a reef full of interesting sea life.
"All of my personal adventures around the area such as kayaking, reefing, long beach walks and so much more, largely helped me with the descriptive storyline."
Walking along the beach one holiday with his sister, Arlo was hit with an idea.
"I was thinking and wondering about what kind of sea life was out there, perhaps animals like dolphins, sharks, turtles or even whales.
"The idea came to me in seconds and it was almost like a flood of pictures and scenes that circled me.
"I ran as fast as I could back to the holiday house, grabbed my laptop and started typing out anything and everything I could to remember this idea."
Five months later Arlo finished the first draft of the book, followed by another six months of editing and perfecting it.
"The book took me about five-six months to write and then at least another six months to edit and perfect.
"The hardest part about the process was probably the editing stage.
"While it felt great to have a book finally finished, it was a lengthy experience to get it to how it is today."
Arlo's mother, Vida, is an experienced book illustrator and designer who has illustrated and designed the cover and inside pages for him.
"Arlo's Dad and I had said for a while that if Arlo wrote a book he was happy with then we would love to help him publish it," Vida said.
"It was great to be able to use my skills as a children's book designer to help Arlo to achieve his dream of having a published book, and was a lovely experience for me too, as he was a very appreciative client."
Vida would regularly show Arlo her drafts of the cover, with Arlo giving feedback along the way.
"I was keen for the illustration and design to reflect what he had imagined for the book.
"It was a different experience to working for other publishers in that we only had ourselves to keep happy, rather than a whole team of people - it was a much more personal project."
Arlo said, "Having my mum's support throughout this adventure of a lifetime has been better than I could ever describe.
"She has done so many things for me to help me get to where I am today and I never could have done it without her.
"It's truly been an incredible journey that has most definitely not finished yet."
The book was financed by Arlo himself, who raised the money from selling previous books and prints of his artworks at the Kāpiti Arts Trail.
It will be available from the end of May in Books & Co, Ōtaki, Paperplus and Moby Dickens in Paraparaumu, and Good Books, The Children's Book Shop and Unity in Wellington along with the Artisan Craft Market at Waikanae Memorial Hall on May 21.
You can also purchase a copy by emailing Vida at vida@kellybuilt.com.
