Five months after his sudden death, Alan Thicke’s sons have decided to take their stepmother to court

BEVERLY HILLS, CA - OCTOBER 23: Alan Thicke and Tanya Callau Thicke arrives at the 32nd Anniversary Carousel Of Hope Gala at the Beverly Hilton Hotel on October 23, 2010 in Beverly Hills, California. (Photo by Frazer Harrison/Getty Images) *** Local Caption *** Alan Thicke;Tanya Callau Thicke

Alan Thicke’s eldest sons are fighting against their father’s widow.

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According to PEOPLE, Robin and Brennan Thicke have filed a lawsuit in L.A. County Superior Court, after Tanya Callau claimed the prenuptial agreement she signed in 2005 before marrying the late actor is invalid.

Thicke reportedly left his sons “in equal squares” ownership of his Carpinteria, California ranch. It was his wish to keep “The Ranch” in his family after purchasing it in 1989. The three sons, Robin, Brennan and Carter were also given “75 percent of his personal effects, and 60 percent of his remaining estate.”

Callau was left with “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, shortly after her husband passed away, Callau made the claim that her prenup is invalid.

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“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 court documents state.

“Now that Alan is dead, Tanya claims there are numerous problems with the Trust and the Prenuptial Agreement,” attorney Alex Weingarten wrote 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 ‘Marvin 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 continued.

Weingarten claimed that Brennan and Robin, who were appointed co-trustee’s of their late father’s estate prior to his death, “made every effort to resolve this without the need for going to court.” He said they only decided to file a lawsuit 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.”

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