A grieving mother has been found dead in her Sydney home just five months after her estranged husband executed their two children in the same house and later turned the gun on himself.

Police were recently unable to reach Olga Edwards, 36, so went to her home on Hull Rd in Sydney's West Pennant Hills to conduct a welfare check this morning and made the discovery.

News.com.au understands her death is not being treated as suspicious.

On July 5 this year, John Edwards, 68, entered his estranged wife's house and shot dead their two children, Jack Edwards, 15, and Jennifer Edwards, 13, in a bedroom, about 5.30pm.

Jennifer and Jack Edwards were shot by their father in July. Photo / Supplied
Jennifer and Jack Edwards were shot by their father in July. Photo / Supplied

Edwards, a retired financial planner, had tracked down the family and hired a car to stalk the children so they would not recognise him when he pulled up outside their home.

He timed the chilling attack just before the end of school term when he knew they would be alone and before their mother and north shore solicitor, Ms Edwards, returned home from work.

Ms Edwards arrived home soon after to the "horrific scene" and collapsed from "severe shock", about 6.30pm. Ms Edwards was understood to be in the care of friends in the days following the tragedy.

The gunman's body was found in a Normanhurst home, about 5km from the scene of the initial killings, about 12 hours after his children were found dead. Edwards lived alone with his dog at the Normanhurst home he bought four years ago.

Police said the murders were "targeted … premeditated and planned" and related to domestic violence amid a two-year custody battle between Edwards and his wife.

Soon after the tragedy, the first pictures of the two children were released to media, at the request of their grieving mother, as she returned home for the first time since the tragic event.

Ms Edwards was seen being escorted by detectives into her rented house where her daughter and son were murdered.

The Edwards children were shot dead by their father in a West Pennant Hills home. Photo / Seven News
The Edwards children were shot dead by their father in a West Pennant Hills home. Photo / Seven News

One neighbour, who didn't provide her name, today told news.com.au she didn't know Ms Edwards but noticed her car was always parked out the front of her home — as if she rarely left — after her children were murdered.

Online fundraising pages were later set up to raise money for Ms Edwards and her mother, who lives in Russia and flew to Sydney to support her daughter.

"Olga's world was completely shattered on 5 July when her ex husband murdered her two teenage children Jennifer 13 and Jack 15 in their own home," a My Cause fundraiser read.

"As Olga was originally from Russia, her only family in Australia was the nurturing and loving family unit she created for her two children in the Sydney suburb of West Pennant Hills.

"Olga's life has been irredeemably changed by an unspeakable crime and we as her community want to assist her in her onward journey by removing the burden of financial pressures and to enable her to focus on her healing.

"More importantly, it provides us all with the ability to show that we care as a community and hopefully that will be a small balm to Olga's soul."

A GoFundMe fundraiser revealed Ms Edwards was "currently in a great distress and will possibly be out of work due to shock & bereavement for some time".

It later emerged that Mr Edwards had left a series of letters for relatives which he handed to a friend days before he committed the double murder then took his own life but it wasn't immediately clear what was written inside.

The murdered teens were part of Mr Edwards' second family after he split from his first wife and two children in 2000 or 2001.

Jack was a student at Pennant Hills High School and Jennifer attended Gosford High selective school.

Mr Edwards had once been the subject to an AVO, there were no apprehended violence orders against him at the present time, thus allowing him to obtain two firearms legally.

He was described as a loner, who was anti-social and abusive to his children.

NSW Police Acting Region Commander Brett McFadden previously told reporters the couple had been in a long-term relationship. However, that had broken down in recent years and Edwards lived separately from the rest of the family at the Normanhurst address where he died.

Mr Edwards — who described himself online as a "certified financial planner" — had owned the Normanhurst house since 2014. News.com.au understands Edwards was self-employed and had been aligned with AMP from 1995 until 2016.

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