She explained that the team at Australia's Lismore Hospital "worked tirelessly to save Harmony" as well as treat her for postpartum hemorrhage, a potentially life-threatening condition caused by severe bleeding after childbirth, per the Cleveland Clinic.

A team of doctors even flew in to help and "continued to spend hours trying to save our little boy," she said.

They did not share their son's cause of death.

As they've mourned their baby, Negara thanked their loved ones who have shown immense support, saying, "Our hearts sit in deep gratitude to our friends who have loved and cared for us this past week."

In the coming days, Negara and Hunter plan to hold a memorial service for their infant on the land of the Bundjalung Nation Aboriginal people.

"We will soon lay our angel to rest on Bundjalung Country where he was born, the land that has held my family and continues to hold our family," she wrote. "We know you will return to us again old soul, we can feel you surrounding us, our Angel."

Hunter—a salon owner—added a touching tribute on his Instagram Story, which read, "The most perfect son a dad could ever ask for. I know you will return to us."