Officials have opened an investigation into the deaths of Oscar-winning actor , 95, and his wife Betsy Arakawa, 65, who were discovered dead in separate rooms of their home in New Mexico on February 26.

It has since been revealed Arakawa had died from a rare virus spread by mice with her death likely to have occurred a week before her husband's on February 11, while Hackman, who had Alzheimer's likely died on February 18 from heart disease.

The couple's sprawling property in Sante Fe is reportedly worth $3.8 million and their other assests amount to $80 million according to celebritynetworth.com.

The gap between their deaths and the different dates of their passing could significantly impact their large fortune, according to Kevin Holmes of Holmes Law Firm, who spoke to the Daily Mail.

It could potentially have implications for any inheritance Hackman's son Christopher and two daughters, Leslie and Elizabeth from his previous marriage could receive. Arakawa, a pianist from Hawaii had no children.

Under New Mexico law, had the couple died within 120 hours of each other their deaths would be classified as "simultaneous". This may have impacted how Hackman and Arakawa's estates would have been divided.

But given investigations found Hackman lived for seven days after his wife, based on pacemaker activity, those provisions would not apply and his assets divided among his beneficiaries, other than Arakawa experts have claimed.

"In a lot of states, including New Mexico, there's a kind of presumptive triggering deadline of five days before you're considered having survived under the terms of most wills," Kevin explained.

While the details of their wills are unknown, Arakawa's early death could mean that her assets would transfer to Hackman rather than her family, and would in turn transfer to whoever the actor named in his will.

It is unknown whether a pre-nuptial agreement had been signed during their marriage and it has not been made public who they had named as beneficiaries to their assets.

Under New Mexico law, family members and others have up to three years of a person's death to file a probate case.

Hackman's two daughters, Elizabeth, 62, and Leslie, 58, and granddaughter Annie, have released a statement saying they were "devastated" by his death.

"He was loved and admired by millions around the world for his brilliant acting career, but to us, he was always just Dad and Grandpa," they said in a statement.