A Texas family is seeking justice for the unexplained death of their mother.

Janice Lee Willhelm was found lifeless with a .45 caliber bullet in her neck. Her death was ruled a suicide, but a Dallas private investigator says that is simply not possible. Now, there are allegations from the victim's children about a forged will.

Willhelm, 63, and her husband called Leon County their home until one dark day in 2010.

"I think my wife just shot herself," Janice's husband is heard telling a 911 dispatcher.

"I was sitting there in the chair asleep and I heard a big bang," he said. "I woke up and she's got blood running out of her neck."

It was a 911 call her husband made purportedly seconds after realizing his wife of 10 years was sitting in the recliner dead.

"I didn't touch her, I didn't touch her," he told the dispatcher.

According to the crime scene photos, the weapon was a .45 caliber pistol. Most of the images are graphic, but show the gun on the floor several feet from where Janice Willhelm had allegedly shot herself in the neck. She had no history of mental illness but did have physical ailments.

"She's been without the medicine, and I didn't think nothing about it," her husband told dispatchers.

That statement to the dispatcher about the medicine would be one of several statements her family says they simply could not ignore.

"None of that was true, she had medication in her system," said her daughter Jennifer Davis.

"My brother and I could not believe that she would have taken her own life," Davis said.

She said her mother never ever spoke of harming herself, so the news of her death was beyond shocking. But then, several months later, something even more puzzling surfaced in the copy of her will.

"I realized immediately that that wasn't my mother's handwriting. Part of it was her writing, but the actual signature in the final pages was not," Davis said.

That's when Davis took her concerns nearly 130 miles north to Dallas County, armed with a folder and the knowledge that there was a former chief of police-turned private investigator willing to listen.

"As I looked at the case and I started looking at the physical evidence and the photographs of the crime scene and how it was handled, I became highly suspicious," said Avery Ensley, of Dallas Polygraph Services.

Ensley started getting second opinions outside of the Leon County Sheriff's Office, the investigating agency on the case.

Ensley says a handwriting expert determined the will was likely forged. According to Willhelm's medical records, a surgery prevented her from lifting her left arm any higher than her chest.

"She would have had to hold the weapon upside down and raise her arm completely up over her head in order to shoot herself this way," Ensley said, demonstrating with his hand.

"My opinion, and also the medical examiner's opinion from San Antonio, was that the weapon was placed by someone else," he said.

According to the autopsy report, the Dallas County medical examiner ruled Janice Willhelm's death a suicide in 2010. Ensley says that doctor's determination was based solely on the Leon County sheriff's report.

"The very same week that I reported to them that the will was forged, the gunshot residue kit from the victim disappeared. It's no longer in existence. Nobody knows where it is, it's lost," Ensley said.

The Leon County Sheriff's Office tells NBC 5 that as far as they're concerned, the case is closed and now in the hands of the Texas Rangers. They added that until further evidence is provided, her death will remain classified as a suicide.

Willhelm's children have filed a civil lawsuit against the woman's husband and claim the will was forged. That case is pending.

The Texas Rangers aren't commenting on the case, but Willhelm's husband is. He allowed NBC 5 to videotape him but not record his voice for fear he might incriminate himself in the ongoing civil lawsuit about the will. He denied all allegations. His story remains the same as the day he made the 911 call.

"It was just clear it was not in her makeup to go out like that," said Davis.

"I am doing everything in my power to take down the person that did this," she said.