She's proven that where there's a will there's a way to get back at relatives you don't like, even after death.

When wealthy resident of Sydney's exclusive Point Piper Harris passed away, she left the entire $12.5 million estate to her next door neighbour Beatrice Gray.

Harris, who died aged 95, was going to bequeath her estate to her relatives, but changed her mind when she felt members of the family were trying to push her out of her house and into a nursing home.

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She switched her will to her neighbour, stating "I give my property and assets to Robert and Beatrice Gray equally".

Not surprisingly, her family contested the will in the Supreme Court in a case that ran for two years.

According to Armstrong Legal's John Sutton "this area of law can get very, very nasty indeed, particularly when the deceased had a number of relationships. So there might be children from each relationship who are challenging it."

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Sutton says "statistically it seems quite often that the applicant, so the person challenging the will, will actually get something out of the challenge."

In this case the court found in favour of the neighbour - noting that they often looked after Harris, helped with chores and regularly did milk and bread runs.

"If one wants to get a water-tight will, it sounds like an advert, but you really need to sit down with a lawyer, particularly a lawyer that knows what they're doing in the area of wills and estates," Sutton said.

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