Riley Keough and her grandmother, Priscilla Presley, are speaking out against new allegations made by Presley’s former business partners in their lawsuit against her.

“We are aware of the latest allegations from Brigitte Kruse. These claims are not only untrue but also deeply hurtful. Our family is, and always has been, united in love and respect for one another,” Keough, 36, and Presley, 80, tell PEOPLE.

The statement continues, “Our shared priority remains honoring Lisa Marie’s memory and protecting Elvis’ legacy with dignity. We will not allow outside voices to divide us or to diminish the strength of our bond as a family.”

The joint statement comes shortly after the Daisy Jones & The Six star’s emotional letter to her grandmother was made public in an amended lawsuit submitted this week in Los Angeles Superior Court.

The filing, brought by Presley’s former business partners Brigitte Kruse and Kevin Fialko, accuses Presley of fraud in the inducement, breach of contract, conversion, misappropriation of name and likeness, and intentional interference with contract and prospective economic advantage.

The letter was sent to Presley shortly after her only daughter Lisa Marie Presley’s death in January 2023.

“Unfortunately Nona as you are taking me to court I am being forced to defend my mother’s wishes legally and publicly which would not have been my choice,” Keough wrote, according to the filing. “It is really hurtful that after years of me trying to resolve your and my mother’s broken relationship and restore our family, you are taking me, of all people, to court.”

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In the letter, Keough criticized how quickly the battle over Lisa Marie’s estate erupted following her sudden death at 54 from a small bowel obstruction.

“I found being called about the will, less than 24 hours after my mother passed and getting emails from lawyers before my mother was even buried, incredibly heartbreaking,” Keough told her grandmother.

Krause and Fialko also claimed in their amended complaint that Presley put “undue [financial] pressure” on Elvis Presley in the spring of 1977, ultimately “pushing him to his death” on Aug. 16 of that year.

A lawyer for Presley additionally denied allegations in a new $50 million civil lawsuit filed against her that accuses her of leading her only daughter to an early death in an alleged plot to regain control of the Elvis Presley estate.

Singer also called the new claims in the amended complaint “despicable,” adding, “Priscilla did not have anything to do with the assassination of JFK, she did not cover up Area 51, she did not fake the moon landing, and she is not secretly keeping Bigfoot locked in a cabin in Canada.”

“Take off the aluminum foil hat and face reality,” Singer continued in a statement to PEOPLE. “This lawsuit concerns Ms. Presley’s claims against Ms. Kruse (and her co-conspirators) in which she alleges that Ms. Kruse engaged in a relentless and calculated campaign of elder abuse and fraud in order to take control of Ms. Presley’s finances for her own benefit. Ms. Kruse’s allegations are absurd and despicable, but unfortunately, are not surprising. Ms. Presley looks forward to holding Ms. Kruse and her co-conspirators liable for their wrongful acts.”

In response, attorney Jordan Matthews of Holtz Matthews LLP, who represents Kruse and Fialko, said, “Apparently, Ms. Presley’s defense is to list off nonsense hyperbolic statements that have no substance. The documents are in black and white and speak volumes. To date, Ms. Presley has presented zero evidence in support of her salacious claims, and we intend to hold her accountable for her reckless behavior.”