HOUSTON — The family of a southeast Texas firefighter killed in a July 4 blaze has sued to void his marriage to his transgender widow and prevent her from getting his death benefits because she was born a man and Texas doesn’t recognize same-sex marriages.

The attorney for the mother of Thomas Araguz III said Thursday that the firefighter only learned of his wife’s gender history and after he found out, he moved out of their home and planned to end the marriage.

But a tearful Nikki Araguz [pictured] said her marriage was not a fraud.

“I’m absolutely devastated about the loss of my husband. I’m horrified at the horrendous allegations accusing me of fraud. They are absolutely not true,” Araguz, 35, told reporters during a brief statement at a news conference.

Thomas Araguz died while battling a blaze at an egg farm in Boling, about 55 miles southwest of Houston. The 11-year veteran of the Wharton Volunteer Fire Department was trapped by falling debris in a burning production building.

In a lawsuit filed July 12 in Wharton County, his mother, Simona Longoria, asked to be appointed administrator of her son’s estate and that her son’s marriage to Nikki Araguz be voided because the couple were members of the same sex.

According to court documents included as part of the lawsuit, Nikki Araguz was born Justin Graham Purdue and changed her name to Nikki Paige Purdue in February 1996.

Voiding the marriage would prevent Araguz from receiving any insurance or death benefits or property the couple had, with these things only going to her husband’s heirs, said Chad Ellis, Longoria’s attorney.

A Friday court hearing is planned to determine whether to extend a temporary restraining order granted Longoria that prevents Araguz from receiving insurance or death benefits or having access to bank accounts or property the couple had.

“Nikki is attempting to make a huge money grab,” Ellis said.

But Darrell Steidley, one of Araguz’s attorneys, said Thomas Araguz was aware his wife had been born a man and that the couple still was living together at the time of his death. The couple had been married for nearly two years.

“We’re going to assert her rights as a spouse of a fallen firefighter,” Steidley said.

Ellis said his client’s efforts to void the marriage are supported by Texas law, specifically a 1999 appeals court ruling that stated chromosomes, not genitals, determine gender.

The ruling upheld a lower court’s decision that threw out a wrongful death lawsuit filed by a San Antonio woman, Christie Lee Cavazos Littleton, after her husband’s death. The court said that although Littleton had undergone a sex-change operation, she was actually a man, based on her original birth certificate, and therefore her marriage, as well as her wrongful death claim, was invalid.

“The law is clear, you are what you are born as,” Ellis said.

While Phyllis Frye, one of Nikki Araguz’s attorneys, declined to comment on what role the 1999 appellate ruling will play in her client’s case, she said the decision “wrecked a lot of lives.”

In April, Texas Attorney General Greg Abbott’s office was asked to give a legal opinion in a separate case on an issue connected to the 1999 ruling.

El Paso County Attorney Jo Anne Bernal asked for an opinion on whether the county clerk’s office could issue a marriage license to two West Texas women if one of the women, who had previously undergone a sex change, presented a birth certificate that identified her as being born a man.

The West Texas couple didn’t wait and went to San Antonio, where Bexar County officials granted them a marriage license, saying they relied on the 1999 ruling. Bexar County has previously issued marriage licenses in similar situations.

Abbott’s office has yet to issue an opinion.