A couple has been found dead in their home while their three-year-old daughter slept.

The neighbours of a couple found dead in a possible murder-suicide on Father’s Day say they didn’t “hear a thing” in the afternoon of their death, and are shocked at how the couple could meet such a tragic end.

Police were called to the home in Smithfield, Sydney just after midday yesterday.

A family member had stumbled upon the bodies as the couple’s three-year-old daughter slept in another room in the house.

The bodies of Tasmin Bahar and her partner of six years Dave Pillay were found in the bathroom of Pillay’s home, just months after neighbours say they had split.

Speaking to Fairfax Media, neighbour John Araco said that despite initially hearing the toddler call out early in the afternoon, they found nothing come of the outburst.

"My wife raced downstairs and said, 'John, the little girl has come out screaming, yelling mummy'," Mr Araco said.

After having a closer look of the house, Mr Araco concluded he did not see anything out of the ordinary that would prompt further action.

"It seemed very quiet so I didn't think anything of it until the police came," the 65-year-old said.

Another neighbour told the Daily Telegraph he also didn't hear anything from the house on Sunday afternoon.

“I wish I had heard some screaming. I heard nothing,” he said.

At this stage, Police say the couple's four-year-old is "unharmed" and "being cared for," while they seek to determine the exact nature of the relationship between the pair.

"One of the lines of inquiry is to establish the relationship between the pair. At this stage no other parties are being sought in relation to the matter," NSW Police said in a statement.

Ms Bahar's sister, Sharagin Bahar also spoke to Fairfax media and said Mr. Pillar had had physically threatened her and her daughter in the past.

"We told her not to go [to the Smithfield house] ... but she went for Father's Day," Sharagin said. "She wanted Dave to see her daughter."

Police are yet to confirm the status of the couple's relationship, and are currently preparing a report for the Coroner.

*Feature image via Facebook/DavePillay.