The mental capacity of Sumner Redstone is at the center of yet another lawsuit, this one filed by Viacom CEO Philippe Dauman against Shari Redstone, the billionaire businessman’s daughter.

Dauman and longtime Viacom director George Abrams filed a legal complaint in the Commonwealth of Massachusetts Probate and Family Court accusing Shari of taking advantage of her 92-year-old father’s mental state in an attempt to gain more control over his companies.

The papers were filed just days after Dauman and Abrams were ousted from the media mogul’s trust and from their positions as directors of National Amusements.

Viacom stock began to rise on Monday after the news of Dauman’s ousting, leading some to speculate that the CEO could also be on his way out at the company. 

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Another one: Viacom CEO Philippe Dauman and longtime company director George Abrams have filed a lawsuit against Shari Redstone (above with daughter Shari in 2012)

Timing: The lawsuit comes just days after Dauman (left) and Abrams (right) were removed from Sumner Redstone’s trust and as directors at National Amusements

‘Shari Redstone is attempting to illegally hijack her father’s well-established estate plan by removing professional managers and reportedly installing her daughter, an employee and a friend who are firmly under her control,’ Dauman said in a statement after filing his legal complaint. 

‘We all continue to have great respect and affection for Mr. Redstone, but he is clearly being manipulated by his daughter, Shari. After years of estrangement, she has inserted herself into his home, taken over his life, and isolated him from anyone not under her control, including long-time business colleagues.’

He later added; ‘Her singular goal is to assume complete control of his businesses, despite Mr. Redstone’s long-term desire for a professionally managed Trust and an independent Board of Directors. 

‘Shari’s actions amount to an unlawful corporate takeover, and if effectuated, could have far-reaching consequences for thousands of shareholders and employees of Viacom.’

Abrams meanwhile spoke about his decision to join the lawsuit, saying; ‘My sole purpose in joining in this lawsuit is to allow a court to determine whether Sumner Redstone, in his current diminished capacity, has been subject to undue influence in his recent actions in changing his Trustees and in changing other document.’

He also noted of the decision to have himself and Dauman removed from Redstone’s trust; ‘The changes purportedly being made would alter his previously and repeatedly expressed wishes. As a result of some of the information which has recently been received, I believe a court test on the question of undue influence is necessary.’

Making things a bit difficult however is the fact that Dauman filed a declaration last year stating that Redstone seemed ‘engaged and attentive’ in response to an action filed against the man by his ex Manuela Herzer.

The complaint filed Monday states that in the months since Dauman made that decleration Redstone’s ‘health has rapidly declined.’ 

The other lawsuit: Redstone’s mental competence was recently challenged by his ex Manuela Herzer (above on May 6) in court

Ruling: ‘There is no good cause for further judicial involvement where the court has heard from Redstone that he lost trust in Herzer,’ said Judge Cowan as he dismissed Herzer’s case (Shari Redstone above with her son Brandon and a lawyer)

‘Mr. Redstone is being manipulated by his daughter, Shari. After years of estrangement, she has inserted herself into his home, taken over his life, isolated him from contact with others, and purports to speak for him,’ states the legal complaint. 

‘In doing so, she is attempting to use his control to dismantle his estate plan to serve her own interests and to assume control of his businesses which he long refused her. 

‘Her attempt to do so, however, is based on exercising undue influence over her ailing father and thereby purporting to seize authority from a man not mentally competent to have granted it.’

The papers go on to say; ‘Shari’s actions are manipulative, invalid and unlawful, and could have far-reaching negative potential consequences, not just for Sumner Redstone but for other members of the Redstone family and the thousands of shareholders and employees of Mr. Redstone’s companies.’

The court papers also lay out how Shari has increased her control over her father’s businesses by ousting Dauman and Abrams and replacing them with individuals who she is closer with, adding that Redstone never gave her control of any of these companies because she ‘did not meet her father’s high standards for managing those businesses.’

The legal complaint also points out two past occasions where Redstone very public tried to buy out his daughter’s stake in his businesses.

‘Shari’s relationship with her father has also been fraught by personal conflict,’ Dauman states in his compalint.

‘Court papers filed under penalty of perjury by Mr. Redstone’s granddaughter and Shari’s niece, Keryn Redstone, state that he had a “very tempestuous and difficult relationship” with Shari; Shari has “consistently expressed hostility” towards him; Shari told one of Mr. Redstone’s grandchildren that “I will get your grandfather, even if I have to hurt you,;” Mr. Redstone “reciprocated Shari’s hostility;” and that “Shari is his daughter, but never bothered to see him.” Mr. Redstone has also characterized Shari as being unqualified and ungrateful.’

Shari was also the only board member who voted against Dauman when he was elected as the Executive Chairman of Viacom earlier this year, taking over for Redstone. 

Claim: Dauman’s lawsuit claims that Shari is taking advantage of her 92-year-old father’s diminished mental capacity to gain control of his companies (Redstone above with Megan Fox in August 2014)

The filing also accuses Shari of using her undue influence to get her father to change his will.

‘Shari participated in effecting changes in Mr. Redstone’s last will and testament in as yet undisclosed ways, the court papers state.

‘In December 2015, she arranged for her father to execute documents purportedly to express his wishes that she would participate in healthcare decisions. 

‘In April of 2016, Shari arranged for the purported execution of a new healthcare directive naming her and her friend as Mr. Redstone’s new healthcare agents. 

‘In the last week, there have been further changes to Mr. Redstone’s will and numerous other documents.’

Dauman and Abrams are now asking the court to invalidate their removal as trustees of Redstone’s estate and as directors of National Amusements.

A representative for Shari responded to Dauman filing court documents on Monday with their own statement, saying; ‘It is absurd for anyone to accuse Shari of manipulating her father or controlling what goes on in his household. Sumner makes his own decisions regarding whom he wants to see both in his home and elsewhere, and he has his own team of independent advisors to counsel him on corporate and other matters.

‘As to the idea that Shari, an attorney and respected businesswoman, would ‘unlawfully’ use his name, that is utterly ridiculous.’

Redstone’s mental competence was recently challenged by his ex Herzer in the aforementioned case in which Dauman filed a declaration saying that the media mogul was in fact mentally competent.

A judge dismissed Herzer’s suit, and she responded by filing another lawsuit just days later.

Herzer, 52, is claiming in her latest suit that Shari and her sons Tyler and Brandon Korff, along with Redstone’s house manager Isileli Tuanaki and lead nurse Jeremy Jagiello, worked together to turn Redstone against his former girlfriend.

The lawsuit alleges that Shari spearheaded the plot, which stripped Herzer of her role as Redstone’s primary caregiver as well as her share of the inheritance.

Herzer is seeking $70 million, plus legal fees, for what she calls ‘criminal acts in intentionally destroying [her] special relationship with Sumner’, which in turn caused him to disinherit her.