Robin Thicke And Brother Brennan Taking Stepmother To Court As She Claims Pre-Nup Is Invalid 

Alan Thicke was laid to rest, his two eldest sons are taking the late actor’s widow to court.

According to court documents obtained by PEOPLE and filed Tuesday in L.A. County Superior Court, Alan’s two eldest sons — Brennan and Robin Thicke — claim in the petition that his widow, Tanya Callau, is now alleging that the prenuptial agreement she signed ahead of marrying the

Prior to his death, Brennan and Robin were named co-trustees of their father’s living trust if his brother, Todd Thicke, declined to take on the responsibility (Todd did decline). In February 2016, the most recent iteration of Alan’s trust was signed; the two brothers allege that Callau did not make any complaints about the estate or prenup at that time, according to the docs.

According to the documents, Thicke, who passed away unexpectedly on Dec. 13 at 69 years old after suffering a heart attack while playing hockey with his youngest son, Carter, left each of his sons “(in equal shares): ownership of the Carpinteria, California ranch that he bought in 1989 and desired to keep in his family forever (the “Ranch”), 75 percent of his personal effects, and 60 percent of his remaining estate.”

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Callau was left “all of the Ranch’s furnishings, 25 percent of his personal effects, a $500,000 life insurance policy, all of his death benefits from pensions and union memberships … and 40 percent share of his remaining estate. Alan also provided that Tanya may live in the Ranch after his death so long as she maintains the property and expenses.”

But in the time since her husband passed away, Callau is now claiming that the prenuptial agreement she signed over 10 years ago is invalid.

“Nonetheless, despite Alan’s generous benefits and careful planning Tanya demands more. Tanya insists the Prenuptial Agreement that she entered into before marrying Alan is invalid,” the documents state.

“Now that Alan is dead, Tanya claims there are numerous problems with the Trust and the Prenuptial Agreement,” attorney Alex Weingarten writes in the petition.

“Tanya asserts that there is no chance the ‘Prenup’ could withstand legal challenge and that she has very significant community rights in the Trust’s assets and rights of reimbursement with respect to improvements to the Ranch. Tanya also claims ‘

rights’ asserting that she had to forego opportunities to pursue and advance her own career in order to support Alan and be his companion and partner, including raising Carter,” Weingarten continues in the petition.

In the documents, Weingarten also claims that Callau has “threatened to make her claims fodder for ‘tabloid publicity’ unless the Co-Trustees agreed to participate in a mediation and succumb to her demands.”

Callau’s attorney Adam F. Streisand, however, tells PEOPLE in a statement: “Tanya Thicke has never threatened to take private family matters public and she never has. It is clear that Alan’s sons have chosen this distasteful public smear tactic to bully Tanya, by stirring up the tabloid media, filing a bogus lawsuit, and refusing family mediation. Tanya is still grieving the death of her beloved husband and out of respect for Alan’s memory intends to handle his sons’ false statements privately.”

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that Brennan and Robin have “made every effort to resolve this without the need for going to court,” Alan’s two eldest children have filed the petition to “honor the memory of their father, protect his legacy, and prevent his testamentary intentions from being undermined by avarice and overreaching of his third wife, Tanya Callau,” the documents state.

Reps for the Thicke brothers did not immediately respond to a request for comment.

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