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Victim Of Florida Serial Killer Identified As Tampa Teen Who Disappeared In 1980

Authorities say that one of two previously unidentified victims of Billy Mansfield Jr. — a serial killer currently serving life for the murders of five people — was 16-year-old Theresa Fillingim. 

By Jax Miller
A police handout of cold case victim Theresa Fillingim

The identity of a serial killer's victim has been discovered, more than 40 years after her remains were found on his Florida property.

The Hernando County Sheriff’s Office descended onto the Spring Hill, Florida property of Billy Mansfield Jr. in the spring of 1981, where they found four sets of human remains, only two of which they were previously able to identity. On Wednesday, however, officials announced they’d finally identified one of the Jane Does as 16-year-old Theresa Caroline Fillingim.

Fillingim was reported missing by her sister on May 16, 1980, just one week shy of her 17th birthday, according to NBC Tampa affiliate WFLA-TV. Cold Case Detective George Loydgren said he believed Fillingim was abducted and murdered that same day.

“Forty-two years is a long time,” Fillingim’s sister, Margaret Johns, told reporters. “Life is short. It can be even shorter for some, and watch your back because there’s a lot of bad people out there that’ll do a lot of bad things to people.”

A police handout of Billy Mansfield Jr.

Billy Mansfield Jr. was the eldest son of convicted child molester William Mansfield Sr., according to WFLA-TV. The younger Mansfield was in and out of prison starting in mid-1970s — including a stint in Michigan in 1977 for sexual misconduct. He was released after only a few months after testifying against his cellmate.

While out on parole in that case, he assaulted two teenagers and found himself back in jail.

His other convictions included battery, kidnapping and sexual assault, according to the Tampa Bay Times.

After his release, Mansfield Jr. took up work at a mushroom farm in Santa Cruz, California where he lived with his brother, Gary. There, Mansfield Jr. met married mother-of-three Rene Saling, 29, at a tavern on Dec. 6, 1980.

The following day, passing motorists found Saling’s partially-clothed body in a drainage ditch in Watsonville, California, according to a 1980 article by the Santa Cruz Sentinel. A post-mortem examination revealed she was sexually assaulted and strangled to death.

Officials looked into the Mansfield brothers and arrested them in Nevada.

But as California authorities conducted their investigation into Saling’s murder, the high-profile coverage prompted an anonymous tipster to call authorities, imploring them to look for 21-year-old missing woman Sandra Graham at the Mansfields' family home in Florida. According to WFLA, Graham had been an employee at a community college and was last seen leaving a bar on April 27, 1980.

Between March and April 1981, officials unearthed four sets of skeletal remains from the Mansfields' 6-acre junkyard in Hernando County.

The first of the discovered bodies remains a Jane Doe to this day. The two previously identified victims were Sandra Graham and 15-year-old Elaine Ziegler, an Ohio teen who disappeared from her family’s campsite near Brooksville, Florida, on Dec. 31, 1975.

According to court records obtained by the Tampa Bay Times, Mansfield Jr., Gary Mansfield, and William Mansfield Sr. sexually assaulted each victim, but Mansfield Jr. murdered and dismembered them.

Mansfield Jr. buried the women and teens in his yard, admitting that he wanted them close by. He never told police who the Jane Does were.

Hernando County officials eventually sought help using DNA to identify the bodies from the University of North Texas and Parabon NanoLabs.

The University of Northern Texas created a complete DNA profile of each victim from their extracted DNA in 2020, but entries into databases yielded no results.

The profiles were then sent to Parabon’s Snapshot to glean more information about what they might've looked like.

“Individual predictions were made for the victim’s ancestry, eye color, hair color, skin color, freckling and face shape,” the sheriff’s office stated. “Parabon’s research developed a profile that was utilized in the identification of the victim in this case.”

The recent identification gave Theresa Fillingim’s loved ones a sense of closure, according to WFLA.

“It gives me peace because I know I didn’t lose her. That she was taken,” said sister Margot Johns. “Now I can stop looking.”

Billy Mansfield Jr. was convicted of Saling’s murder in California and sentenced to 25 years to life, according to WFLA. He later pleaded guilty to murdering the four victims found in Florida and received four additional life sentences.

Mansfield Sr. was convicted in 1980 for dozens of sex-related charges, including the repeated assault of a 9-month-old girl, according to the Tampa Bay Times. He was released in 1990 but convicted on new charges in 2006. He remains on Florida's sex offender registry.

Gary Mansfield was charged with accessory after the fact for Saling’s murder, but he turned state’s witness and was relieved of the charge, according to ABC Orlando affiliate WFTV.

In 2020, Gary’s home — which is near the property where his brother killed his victims — was the subject of a drug bust, prompting Gary to lead authorities to something “suspicious” on the property.

The suspicious find would transpire to be more human remains, according to WFLA. Little could be found about the 2020 discovery, and Oxygen.com did not receive an immediate response from officials.

According to CBS Jacksonville affiliate WJAX-TV, William Mansfield Sr. lived at his other son's property during the 2020 search.

Jail records reviewed by Oxygen.com show Mansfield Jr., now 66, is still serving his life sentences at the California Health Care Facility in Stockton.