In the most recent court ruling on May 12, a judge denied Hopper's motion to exclude Galen from his life insurance policy, entitling her to a portion of the remaining $750,000, along with Hopper's three older children, Marin, Ruthanna and Henry.
Duffy-Hopper has accused his three adult children from previous marriages of masterminding the divorce and trying to exclude her from his estate.
"Victoria's prime objective is to make sure she can support her child," her lawyer told ABCNews.com last month. "The adult children are taking control of this case and attempting to limit any funds that go to Victoria or Galen, and it really is quite sad. It's the stuff that movies are made of."
"The adult children are clamoring to secure as much money for themselves as possible," Royston said.
The Mayorases, who have written about other estate battles of the rich and famous in their book "Trial & Heirs: Famous Fortune Fights," say Duffy-Hopper is also likely to argue Hopper's "competency" when he made his estate plan and whether his adult children had "undue influence" on him at the time.
Hopper said in previous filings that he had already set up estate for Galen and his three other adult children to receive a "substantial portion."
"Even if he meets the test for mental competency, Victoria could still argue he that he had been unduly influenced," Andrew said.