He was reportedly seen wearing a blue forensic suit at the scene.
“He is a relative and he is being very cooperative and is assisting police with the investigation,” Serafim said.
“My staff who attended as first responders and also the emergency services from the Queensland Ambulance Service have entered a scene that is quite traumatic, and these officers and the paramedics are receiving internal counselling in relation to the incident that they were exposed to.”
Neighbour Chris Symes told ABC the situation was “heartbreaking” and he had the seen the girl in the street just a few days ago.
“It’s heartbreaking, this shouldn’t happen, it’s just terrible,” he said.
“Humans, adults you can, sort of, understand but … a little child. That’s terrible.”
Other locals expressed shock on social media.
“My heart goes out to this family, I cannot imagine what they must be feeling. RIP little angel,” one person wrote.
“This is my neighbourhood, our community, I’m crying, total shock, hold your loved ones even closer, what is happening to this world!” another offered.
The 46-year-old woman is due to appear before Southport Magistrates Court this morning.