WHARTON, TX --There are new developments in the case of Nikki Araguz, the wife of a firefighter who died in the line of fire. Since the death, she's been fighting to prove she's female. She was fighting to prove she is a woman to lay claim to about $600,000 in death benefits that the fallen firefighter's ex-wife says should go to his two small children. But late Tuesday, a judge ruled their marriage was not valid. A massive fire at an egg farm in 2010 killed a firefighter in the line of duty and set into motion a controversial battle over $600,000 in death benefits. But Tuesday Wharton County Judge Randy Clapp ruled the marriage between transgender Nikki Araguz and firefighter Thomas Araguz was void. Attorneys for Araguz's ex-wife, Heather Delgado, and his two small boys argued that Nikki was born a male, did not undergo reassignment surgery until months after the marriage and, furthermore, only changed the gender on her California birth certificate two weeks after Araguz's death. "So at the time of Thomas' death, the court's ruling would reflect that Thomas and Nikki were of the same gender, male, at the time of his death. That effectively eliminates for an argument of common-law marriage between the two," Delgado's attorney, Ed Burwell, said. Nikki has said all along Araguz was fully aware of her past as a man and that their marriage was valid. Attorney John Nechman, who tries many gay, lesbian and transgender cases, says the ruling is disappointing, but the fact that Nikki's reassignment surgery after the marriage left the judge little choice. "That was just more impetus for the court to utilize case rulings that have already come forth in Texas, to in essence establish and find that Nikki Araguz was male at the time of marriage, though anybody viewing her would be of the belief that she was female," attorney John Nechman said.