Evelyn and Hortense Edwards spent two decades visiting what they thought was their mother's grave - only to discover it contained the remains of a stranger

Now, the sisters are suing, seeking want $25 million in damages from Rosehill Cemetery in Linden, New Jersey, for emotional distress caused when they learned that their mother, Beatrice Williams, had been buried in the wrong plot.

"It was devastating for them," Mark Crawford, the sisters' attorney, said in a telephone interview.

He said they only recently discovered the mix-up after complaining to the cemetery that what they thought was their mother's grave, which they visit regularly, was falling into disrepair.

An employee looked up the plot in question.

"She said, 'There's a man buried there,' and they said, 'What do you mean there's a man buried there?'," Crawford said.

The complaint filed in Brooklyn Federal Court says the cemetery has acknowledged that the plot location in the sisters' paperwork -- Section 52, Row 20, Grave 103 -- was incorrect.

That error caused the sisters to have "visited the wrong gravesite, sought comfort from the wrong grave, laid flowers on the wrong grave, (and) prayed and had confidential conversations at the wrong grave," it said.

In a letter sent to the sisters last July, the cemetery said it believed their mother was in fact buried in Section 52, Row 20, Grave 132, the complaint said.

A woman who answered the telephone at the cemetery's main office on Tuesday declined to comment before hanging up.

Crawford said the sisters believe that if the cemetery management could be mistaken once, it could be mistaken again, and are not convinced that the cemetery has not misplaced their mother's remains.

They want the cemetery to disinter the remains at the second grave to confirm the remains there are of their mother.

The cemetery management has said it will only do so if the sisters take responsibility should the cemetery still be mistaken and, for example, the relatives of whoever is buried at Grave 132 discover their loved one's remains were unnecessarily disinterred and decide to sue, Crawford said.

"They're not willing to take the risk of correcting their own mistake," he said.

The sisters, who live in the New York borough of Queens, had bought three plots at their mother's death in the hope that they might one day be buried by her side.

Crawford said he did not know the identity of the man buried beneath Beatrice Williams' grave marker. Nor was he certain whether the mix-up was restricted to just two sets of remains -- that Grave 103 actually contains the remains that should be in Grave 132, and vice versa -- or whether other plots were similarly mislabeled.