A Houston woman who went missing in 2015 -- and whose bones were found inside the walls of her home last year -- may have died after falling through the attic floor.

Officials with the Harris County Institute of Forensic Sciences last month definitively identified the bones as those of Mary Stewart Cerruti, 61, who vanished without a trace in 2015. Her cause of death could not be determined, but following months of investigation, detectives feel confident that the mystery of Cerruti’s disappearance has been solved.

"In the attic, there was a broken board that led down to the space," Tricia Bentley, a spokeswoman for the coroner, told People. "Law enforcement thinks she may have been up in the attic and fell through the attic floor."

The Houston Chronicle reported that Cerruti could not be identified through dental records, which detectives were unable to locate, and the results of DNA taken from a tooth and compared to that of a cousin, her closest living blood relative, were inconclusive.

Ultimately, technicians with the Institute of Forensic Sciences used Cerruti’s jawbone, along with photos and video of her, to conclude that the bones were hers, the newspaper said. Sharon Derrick, identification manager at the facility, said that a photo provided by Cerruti’s former employer showed that the shape of her chin and jaw matched the shape of the jawbone found.

A video of the normally reserved and solitary Cerruti speaking at a February 2013 Houston Planning Commission meeting also aided in the identification by showing that, when she spoke, she had difficulty moving her jaw and appeared to speak slowly and with concerted effort, the Chronicle reported.

The movement of her jaw as she spoke corresponded with a condition that forensic experts found in the jawbone, Derrick said. She called the determination that the remains were those of Cerruti a “comprehensive identification.”

The new details, plus the fact that the bones were found in Cerruti's home and autopsy findings showing the remains were consistent with a small, frail woman over the age of 40, painted a picture.  

"We added all the other information that we had," Derrick told the Chronicle. "We never just do a best guess."

Houston police investigators this week released case files on the Cerruti investigation, including photos from the scene inside her home in the Heights area of Houston. The pictures include images of Cerruti's skeletal remains.

Other photos show red-framed eyeglasses similar to those Cerruti wore, as well as a tattered pair of sneakers, all of which were found with the bones. Photos of the attic floor show a missing wooden plank.

A photo looking down into the space below the attic and between two walls of the house show deteriorated fabric and skeletal remains. The most prominently visible part of the remains is the skull.

The bones were removed from the space after firefighters tore through a bathroom wall, the newspaper reported.

According to the Chronicle, the files also included audio of the 911 call from the new tenant in the house, which had been sold at foreclosure following Cerruti's disappearance.

The unidentified tenant made the call just before 2 p.m. on March 4, 2017.

“So, I just called to report this,” the man said, according to the recording. “I didn’t know exactly how to do it, but I just moved into this house. I’m renting it, just moved in a couple days ago, and I found, between two of the walls, I found a human skeleton.”

Hear the entire 911 call below.

Cerruti’s former home on Allston Street appears fairly unique. The small, blue one-story bungalow is surrounded, on three sides, by an apartment complex.

The Chronicle reported that, before she died, Cerruti was the sole holdout against the developer who sought to build the massive apartment building. Despite her fight, which included making the public statement seen on the 2013 video that helped officials identify her, the apartments went up.

In a Google Street View image taken in June 2015, three months before Cerruti was reported missing by concerned neighbors, the apartment complex was under construction, scaffolding hiding its towering façade. Cerruti’s house, then painted yellow, was nearly hidden by an overgrowth of brush and an unmanicured lawn.

Her car sat in the driveway, a portion of which was also overgrown with grass.

The Chronicle reported last year that neighbors had noticed a broken window, and that Cerruti's mail had started piling up. A sign went up announcing the house was for sale.

The Houston bungalow of Mary Cerruti is pictured in a Google Street View image from June 2015. Cerruti, who was last seen months before, was reported missing that August after friends and neighbors noticed her overgrown grass, a pile of mail and a broken window on her home. Her skeletal remains were discovered in a wall of the bungalow in March 2017.

Credit: Google

icon to expand image

Credit: Google

A friend ultimately reported her missing that August after she stopped returning his phone calls, the Chronicle reported. A missing person flier issued by the Houston Police Department stated that Cerruti had last been seen in either February or March.

Police now know that Cerruti was in the house the entire time, her body wedged inside the walls.

It is still uncertain exactly when Cerruti died. The Chronicle reported that the friend who filed the missing person report went to her home and fished some of her mail out through the broken window.

Bills showed that she made several purchases in May, so she was still alive at that point.

In June 2015, an animal cruelty case was called in at the home. The person who responded to that call told police the ladder to the attic was pulled down when they got there, the Chronicle reported.

No additional details of the cruelty case were included, but the newspaper reported that Cerruti had several beloved cats who perished in the home after she vanished.

At the time that her bones were found, Cerruti’s neighbors expressed despair, and even some guilt, over the fact that her disappearance had gone unnoticed for months, and that her body remained undiscovered for so long.

"I wish I knew what more we could have done, how we could have pushed it farther to get somebody to do something else," neighbor Roxanne Davis said.

Cerruti’s cousin, Nancy Stewart Stoddard, told the Chronicle that she still believes there could have been foul play in her cousin’s death.

"I think I'm glad that it's coming to a conclusion," Stoddard said. "I still have lots of questions that probably will never be answered."