"They didn't have enough people so I was sent a message and asked if I wanted to help."
The mother and grandmother said she's been busy distributing flyers and putting up posters in the hope of making the Palmerston North event one of New Zealand's biggest.
"We've had meetings with the courts to ensure we have everything sorted such as traffic management and we really want people to know this is going to be a peaceful protest."
The march will begin at 9am and will finish in The Square, where public speakers will address the topic of child abuse.
"The response we have had so far has been huge ... it's amazing," Ms Fisher said. "There are so many people sick of reading these stories; it's our time to say we want change and we want to stop this plea bargaining."
Shailer and Haerewa were originally charged with Moko's murder but then pleaded guilty to a downgraded charge of manslaughter.
"I have my own 10-month-old grandson and we often sit here thinking, 'how could someone ... ?'," Ms Fisher said.
"We know the public is completely behind us."
The Palmerston North City Council has also offered organisers its support by lighting the clocktower in blue from Monday.
Those wanting to participate can bring along their own signs and are being encouraged to sign a petition asking the Government to stop downgrading murder charges. A Givealittle page has also been established by organisers to fund a referendum to change the legislation surrounding plea bargaining.
March for Moko, Palmerston North courthouse 9am, Monday June 27. For more information visit Facebook: Stand up NZ - Justice for Moko.
