Slain teen’s remains identified four decades after they were discovered at serial killer’s ‘House of Horrors’

Billy Mansfield Jr serving life sentence for murdering five women between 1975 and 1980

Remains found inside a Florida serial killer’s “House of Horrors” more than four decades ago have been identified as those of teenager Theresa Caroline Fillingim.

The 17-year-old disappeared in Tampa in 1980, and a year later law enforcement found four sets of human remains at the family home of Billy Mansfield Jr.

Two of the victims were immediately identified, but authorities were unable to identify the other two sets.

Now, thanks to advancements in DNA technology used in cold cases, one of those sets has been finally identified as  Fillingim.

Samples of her remains had been unsuccessfully sent to laboratories over the years but her DNA profile was not developed until 2020, says the Hernando County Sheriff’s Office. The identification was carried out by the University of North Texas and Parabon Nano Labs.

Investigators used Parabon’s “Snapshot DNA Phenotyping” to produce new trait predictions for Fillingim, the sheriff’s department said in a statement.

Billy Mayfield Jr (California Department of Corrections)

The new profile created new leads and a DNA sample taken from Fillingim’s sister, Margaret Johns, confirmed her identity after 42 years.

“It gives me peace because I know I didn’t lose her, that she was taken,” Ms Johns told WFLA. “The sad part of it is my whole family never knew what happened to her. My dad died without knowing, my mom died without knowing.”

Mansfield is serving a life sentence in a California prison after he was convicted of murdering five women between 1975 and 1980.

He was arrested in California in 1980 for raping and strangling Rene Sailing, 30, after which police received an anonymous tip to search the family home in Florida.

At the property, which was also a junkyard, police found the remains of 15-year-old Elaine Zeigler, 21-year-old Sandra Graham, and Fillingham. The fourth woman still has not been identified.

The women were all sexually assaulted by Mansfield, his brother Gary, and their father, William Mansfield, according to court records obtained by The Tampa Bay Times. But it was Billy Mansfield who killed the women, which he pleaded guilty to in court after his arrest.