SPRING HILL, Fla. (WFLA) — After 42 years, a Florida woman said her family has finally gotten some closure after being notified that the remains of her teenage sister, who went missing in 1980, were found at a Spring Hill home that once belonged to a serial killer.

Margaret Johns told WFLA that the Hernando County Sheriff’s Office confirmed to her that the remains of her sister, Theresa Caroline Fillingim, were found at the home of convicted serial killer Billy Mansfield Jr.

WFLA reached out to the Hernando County Sheriff’s Office for confirmation but a spokesperson said they could not comment, and the cold case detective who Johns said she was in touch with could not be reached.

Theresa Caroline Fillingim (Credit: Margaret Johns)

Johns said she first reported Fillingim missing in 1980. Fillingim was 17 years old at the time. After years of no news, Johns said she was contacted last July by the Hernando County Sheriff’s Office about her sister. Shortly after, Johns said, a police officer in Cape Coral, Florida, where she now lives, visited her to establish a timeline and get a DNA sample.

“So that’s how I found out, and then it’s hurry up and wait,” she said. “You know, you have to wait for the DNA sample to be clear, to be positive.”

She said she then kept in close contact with a cold case detective from the Hernando County Sheriff’s Office. Six weeks after her initial contact with law enforcement, she said, the DNA sample they took came back positive.

“It gives me peace because I know I didn’t lose her,” Johns said. “That she was taken.”

Johns said her sister’s remains were recently brought to the medical examiner’s office in Hernando County.

“I had to wait for them to gather all of her remains because they got shipped off to different universities for identification purposes and facial recognition things — all the modern stuff,” she explained.

She told WFLA she now has to designate a funeral home for the remains to be delivered to so her family can properly say goodbye. Johns said she plans to cremate the remains and split the ashes with her brother.

“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 … my sister died without knowing,” Johns said. “I have a niece that knows, and I have a cousin I keep in touch with that knows what’s going on, and then, besides my brother, that’s it. It’s just the four of us.”

Johns said she’s sharing her story now to encourage other families who may be looking for closure not to give up hope.

“You never know what’s going to happen in your life that’s going to turn up something that you’ve been looking for forever,” she said.

She said she also wanted to give credit to the Hernando County Sheriff’s Office cold case detectives she worked with for “the diligent work… [they] did in bringing her home to me.”

Mansfield was convicted and sentenced to life in prison in 1982 for killing five women in California and Florida.

Johns told WFLA she hopes he “lives out his last days” in prison. She said she has considered confronting him but “I don’t know what that would serve as closure for me or my sister.”

Mansfield’s murders came to light after he raped and strangled René Saling in 1980. Mansfield dumped the body of the mother of three in a ditch near a campground where he was staying with his brother, Gary Mansfield.

While California police were investigating Saling’s murder, Hernando County authorities said they discovered four bodies at Mansfield’s family home in Spring Hill, each in different stages of decomposition. Two of the bodies were identified as Elaine Ziegler, a 15-year-old girl from Ohio, and Sandra Jean Graham, a Tampa woman who went missing on April 17, 1980.

Court documents said the women were sexually assaulted by both Gary and Billy Mansfield along with their father, William Mansfield Sr., who was a convicted child molester. Authorities said Billy Mansfield Jr. would then kill the women, dismembering them.

After a mistrial and attempted prison escape, Mansfield was convicted in Saling’s death and pleaded guilty to the other four murders in Hernando County. He also pleaded guilty to attempted sexual battery involving a fifth victim.

Forensic experts searched the Mansfield home again in October 2020 after Gary Mansfield was arrested for drug possession. During their search, more human remains were found.