Ms Harkin told BBC News NI that she wanted to write a book specifically for children.
“My family and I know so many people this affects, and I understand how difficult that conversation with kids can be,” she said.
She graduated last summer from Queen’s University Belfast’s broadcast production programme, and her final project was a documentary about defective concrete blocks.
“Working on that inspired me to explore other creative projects around this issue,” she said.
“After graduating, I worked as a special needs assistant in a primary school, where I was in contact with so many children in affected communities, which sparked the idea for the story.”
She said she wanted to keep the book “melodic and light for young ears, but without downplaying such a huge issue”.
“It took a number of rewrites to balance the harsh reality some children face with a positive, child-friendly outlook,” she added.