POLICE are investigating whether drowning or poisoning could have killed four-year-old Eeva Dorendahl-Hutchings after no weapons were found at the crime scene on Pottsville Beach.
News Corp reported that officers seized items from the scene but it's believed no guns, knives or rope were found near her body which was discovered on Tuesday under a pandanus tree alongside her dad Greg Hutchings.
An autopsy will be conducted on both bodies today but police say the badly-decomposed remains, which may have been in the dunes for more than two weeks, will make determining the cause of death difficult.
Police have confirmed they are investigating an apparent murder-suicide but the cause of death will be determined by the NSW Coroner.
They are understood to be looking at drowning as one possible cause of Eeva's death.
The tragedy has been hard felt in the Tweed area as well as on the Sunshine Coast where Eeva and her mother lived at Kin Kin.
Detectives on Wednesday visited the Pottsville unit Mr Hutchings, 35, shared with his mother Diana, to take DNA samples, News reported.
Eeva's grief-stricken mother Michelle Dorendahl spent several hours with detectives but is yet to speak publicly.
Diana Hutchings says she does not believe her son was involved in a murder-suicide.
"We are shocked, we need to process it and to show respect for two beautiful people," she said.
"She was a beautiful girl and he was a beautiful man as well.''