Kiwi mum, son found dead in Sydney apartment

Kiwi mum, son found dead in Sydney apartment
Police are investigating it as a possible murder-suicide (Stacey Docherty / Facebook)

The body of a Kiwi mother and her four-year-old son have been found in a Sydney apartment.

Police were called to the Hillside residence at 1:30pm on Monday after the woman's ex-partner visited but no one answered the door, according to the Sydney Morning Herald.

Stacey Docherty and her son Seth were discovered inside.

Forensic officers are treating it as suspicious, and are investigating whether the deaths were a murder-suicide or whether a third person was involved.

Ms Docherty's Facebook says she is a New Zealander working as a nursing assistant.

Neighbours told the Daily Telegraph she had history of police callouts, and Family and Community Service workers were regularly involved in the family.

They say the system "failed" Seth.