Four year old Eeva Dörendahl went missing in January 2014 after spending Christmas with her father Greg Hutchings, 35.
After 17 days of searching, she and her dad were found dead under a pandanus bush in sand dunes north of Pottsville, NSW.
An inquest in March 2019 found Eeva died as a 'result of her father's actions' but a cause of death was never confirmed.
The inquest hear that by the time Eeva was two years old, the relationship between Michelle and Greg was 'irreconcilable' and they had separated.
Now, Michelle has written a letter to explain Greg's behaviour in the lead up to her daughter's death.
She said that before she'd fallen pregnant they'd been in love but then his behaviour changed.
'Once I was pregnant, his behaviour began escalating,' she wrote. 'When our daughter was two years old, I found the strength to leave him. I wanted a better life for Eeva and for myself.
'He was not happy with my decision to separate and told me he would take me to court and take Eeva away from me.'
She said he was abusing prescription drugs and alcohol and she became anxious about her daughter spending time with him. However, he presented well during family court proceedings which is why he had access to Eeva.
As he wasn't physically violent, Michelle says it made it very hard to prove he was dangerous.
'I had nothing I could prove during our family law proceedings. He was intelligent and well spoken, presented well … I felt pressured to give in. He simply used the family law system as part of his control and manipulation of me.
'That my daughter Eeva is not here today is a direct result of the failings of the system.'
Michelle doesn't know who from parliament she will meet with regarding her tragic case but will venture into Parliament House this week with her letter in hand in the hope to make a change.
If you’ve been affected by anything in this story and need help, call Lifeline 13 11 14 (Aus) or 0800 543 354 (NZ) or go to this website.