When Alan Thicke died in December of last year, he likely thought he had made his last wishes clear with a series of court documents, including a living trust. However, several members of his family have been in negotiations over money and property for months and, after finding no common-ground, they will be moving the dispute to the courtroom. Thicke's sons Brennan and Robin filed a complaint in L.A. Superior Court on Tuesday.

Widow may be attempting to annul a prenuptial agreement

According to claims by Brennan and Robin -- who are also co-trustees of Thicke's living trust -- the "Growing Pains" star's wife of 11 years, Tanya Callau, may be trying to invalidate the prenuptial agreement signed by the couple.

If the agreement were to be voided in court, Callau could be entitled to a much larger portion of Thicke's estate.

According to THR, Thicke left his sons, including 19-year-old Carter, equal shares of an 11-acre ranch he owned in Carpinteria, CA, plus 75% of his personal effects and 60% of his remaining estate. Meanwhile, Callau was bequeathed 25% of his effects, all insurance and pension benefits, and the remaining 40% of his estate. The estate was estimated to be worth at least $400 million at the time of his death.

Callau claims Thicke promised the ranch to her and has a prenuptial to prove that she deserves a 1/4 share in its ownership, in contradiction to the trust signed by her late-husband in 2016.

Her lawyer in the proceedings, Adam Streisand, has made his feelings about the agreements and Thicke's former lawyers very clear saying, "It’s a mess because of lawyers who probably should still be writing with crayons."

Thicke made majority of wealth prior to meeting wife

Thicke's sons believe the prenuptial agreement between their father and Callau should be clear, as Thicke earned most of his substantial wealth from his acting career in the 1980s and 1990s.

He also composed a number of theme songs for television series in the 1970s, including "Diff'rent Strokes" and "The Facts of Life."

According to the sons' attorney, Alex Weingarten, Callau did not indicate any concern about her prenuptial agreement until after her husband's sudden death. It was only after his passing "when we started getting claims that ‘The prenup’s not valid, he promised X, Y and Z," he said.

Weingarten also claims that Thicke's widow threatened to bring her assertions to the tabloids "unless the Co-Trustees agreed to participate in a mediation and succumb to her demands," while his own clients are simply trying to honor their father's legacy.

In a statement of response to THR, Streisand contends that Callau did not threaten to speak to the media about her concerns, nor has she tried to bully anyone into mediation. He calls the sons' claims a "distasteful public smear tactic" and goes on to call their Lawsuit "bogus."

There is no court date scheduled to hear the claim filings.