Riley Keough found it "really hurtful" when Priscilla Presley disputed Lisa Marie Presley's will.

The Daisy Jones and the Six actress' grandmother disputed a 2016 amendment to her daughter's last wishes - which removed her as co-trustee and naming Riley and her brother Benjamin, who has since died, instead - and an emotional letter the 36-year-old star allegedly wrote amid the row has been made public as part of an amended lawsuit in Los Angeles Superior Court.

Priscilla's former business partners Brigitte Kruse and Kevin Fialko have accused the 80-year-old star of fraud in the inducement, breach of contract, conversion, misappropriation of name and likeness, and intentional interference with contract and prospective economic advantage and the personal note is one of dozens of items submitted as part of their evidence.

According to People magazine, the note read: "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.

"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."

The letter also detailed Lisa Marie's plans to take legal action against Priscilla before she passed away.

It read: "I have protected you from lawsuits from my mother, often advocating for you and always tried to keep everyone operating out of love.

"Even a few weeks before my mother passed she wanted to sue you again and you called me for help. I advised her so strongly against it, which resulted in a fight between me and her. But as you know she chose to listen to me and not sue you.

"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."

The lawsuit alleged the Naked Gun star "ignored" Riley's "pleas" and instead "manipulated" her with "claims that she 'loved' her and they 'needed to be a family.'"

The message, Exhibit 36, has been presented as evidence that Lisa Marie was preparing legal action against Priscilla shortly before her death and that Riley personally intervened to prevent it.

Brigitte and Kevin alleged they had "sprang into action to prevent Priscilla's financial ruin and public embarrassment" and describes Priscilla as a "calculated sociopath and master of deception, who has lived off of and exploited the 'Presley' name for her own personal gain."

The Naked Gun actress' lawyer, Marty D. Singer, has branded the case "despicable".

He said in a statement: "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.

"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, Brigitte and Kevin's own lawyers hit back and vowed to hold the veteran actress "accountable for her reckless behaviour".

Jordan Matthews of Holtz Matthews LLP, said in a statement: "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 behaviour."