UPDATE, 7:05 PM: A L.A. judge today denied Keryn Redstone’s request to join Manuela Herzer’s health care lawsuit over Sumner Redstone. With this latest development and settlement talks still off, the nearly 5-month long legal battle is still headed for a trial set to start in early May.

Just a day after filing her petition to join the lawsuit, the younger Redstone was informed by L.A. Superior Court Judge David Cowan on Wednesday that she can’t formally join her grandfather’s former companion and health care agent’s action. However, Keryn Redstone can participate in the trial. “Judge Cowan ruled that Keryn Redstone will testify, and therefore the game-changing testimony she sets forth in her declaration will be presented at trial,” said Ira Steinberg, one of Herzer’s Greenberg Glusker Fields Claman & Machtinger LLP attorneys.

PREVIOUS, April 19 PM: Manuela Herzer, who is suing Viacom and the Redstone family to be reinstated as mogul Sumner Redstone’s health-care representative, added fuel to her side today in the latest twist in the contentious battle. As part of an ex parte application (read it here) filed today in Los Angeles Superior Court, Redstone’s granddaughter Keryn Redstone has requested to be added as a petitioner with Herzer in “seeking to invalidate any and all Advance Health Care Directives that Sumner Redstone signed after October 16, 2015.”

This is the latest twist in the ongoing, convoluted and oftentimes embarrassing lawsuit first filed in November over who should decide what with regard to Redstone’s health and well-being. Currently, Viacom CEO and chairman Philippe Dauman is Redstone’s health-care agent and would make decisions for the ex-Viacom chair if he were unable to do so himself. Herzer has claimed Redstone did not sign the papers giving the role to Dauman.

A settlement in the case had been discussed as late as last week, but those talks broke down.

In one of three declarations filed today, Keryn Redstone painted a behind-the-curtain picture of Redstone’s condition and health status at his home in Beverly Park. The 34-year-old daughter of Sumner’s estranged son Brent —  who said she affectionately called her grandfather “Grumpy” for her entire life — used the majority of her 12-page statement (read it here) to cast Sumner’s daughter Shari as a catalyst for bad blood in the family. “Shari has consistently expressed hostility toward me, my father, and Grumpy in sometimes dark, threatening ways,” she wrote. “For example, on at least five occasions I can recall spanning from 2005 to 2011, Shari said to me, ‘I will get your dad, and I will get your grandfather [Grumpy], even if I have to hurt you [me] to do it.’ “

According to Keryn’s declaration, in September 2014, after several bouts of pneumonia, Sumner was admitted to the hospital and needed a feeding tube. “I clearly heard Shari state her beliefs as to what should happen to Grumpy,” she wrote. “She said, ‘If he gets sick, don’t take him to the hospital. Let him die at home.’ Grumpy, being Grumpy, interjected — ‘I don’t want to die!’ Shari proceeded as if Grumpy were not there and as if he had not just expressed his will to live, stating: ‘He wants to die at home. Don’t call the doctors.’ Shari similarly pushed for a ‘do not resuscitate’ order to which Grumpy vehemently objected.”

Shari Redstone has been vying with Dauman over control of her ailing father’s media empire which includes 80% stakes in Viacom and in CBS. Both are members of the seven-person trust that will take control of his holdings when he passes.

In February, after claims from Herzer’s team that Sumner Redstone’s advanced age and declining health require minimal delay, the trial in the case was scheduled for May 6-12.