Nathan was rescued by a firefighter after more than a week at sea.
The lawsuit says the sisters “ask the court to declare that the murderer was Nathan Carman, John’s grandson, their nephew, and that Nathan committed this heinous act out of malice and greed.”
The lawsuit also said Nathan Carman stands to inherit millions of dollars from his mother and grandfather’s estates.
The action Linda's sisters are asking for would bar Nathan Carman from receiving any of Chakalos' $40 million estate.
Nathan Carman, who lives in Vermont, does not face any criminal charges and has denied killing his mother and grandfather.
A statement was released by the sisters' attorney, which says "In 2013, four sisters suffered an unthinkable tragedy when their father John Chakalos was murdered in his own home. Less than three years later one of those sisters, Linda Carman, disappeared at sea under highly suspicious circumstances. The last person to see both of these family members alive was Nathan Carman, John's grandson and Linda's son. The details and evidence in the death of John and the disappearance of Linda all point to Nathan as the prime suspect. Yet he now stands to inherit millions of dollars from their estates. The surviving sisters cannot stand idle while their father's killer, and perhaps their sister's killer also, profits from his actions. Since the law has a provision to stop this unjust inheritance, they have filed a so-called ‘slayer action’ in New Hampshire State Court to block Nathan from collecting money from his murdered grandfather's estate. This is not about money, it is about justice. If the Chakalos sisters win this lawsuit and any money that would have gone to Nathan instead goes to the surviving sisters individually, they pledge to use those funds exclusively to pay for expenses incurred relating to the investigation into the death of their father and disappearance of their sister, and any remaining funds will go to charity. The Chakalos sisters did not undertake this action lightly. This entire ordeal has been extraordinarily painful to the family and the public attention has made it even more difficult. However, they also know this is the right thing to do, and it is what their father and their sister would have wished.”
Thursday, July 27 2017 5:53 AM EDT2017-07-27 09:53:56 GMT
Floyd Mayweather Jr., left, and Conor McGregor exchange words during a news conference at Staples Center Tuesday, July 11, 2017, in Los Angeles. The two will fight in a boxing match in Las Vegas on Aug. 26. (AP Photo/Jae C. Hong)
Movie theaters around the U.S. will show the Aug. 26 fight between Floyd Mayweather Jr. and Conor McGregor.
Thursday, July 27 2017 8:38 AM EDT2017-07-27 12:38:45 GMT
The Emerald Princess cruise ship is docked in Juneau, Alaska, Wednesday, July 26, 2017. The FBI is investigating the domestic dispute death of a Utah woman on board the ship, which was traveling in U.S. waters outside Alaska. (AP Photo/Becky Bohrer)
Federal authorities planned to announce charges in what was described as a domestic dispute aboard a cruise ship in U.S. waters off Alaska that led to the death of a 39-year-old Utah woman.