California authorities identify final unknown victim of 'Happy Face Killer' Keith Jesperson after 34 years

McWhorter's body was discovered Aug. 30, 1992, along Highway 95 about seven miles north of Blythe, California.

Jesperson told investigators he knew the woman as "Claudia," but authorities were unable to determine whether that was her real name.

McWhorter's sisters, who grew up with her, had spent decades without knowing what happened to her after she disappeared from Texas in the 1990s, according to prosecutors.

The district attorney's Division of Victim Services is working with McWhorter's family as they decide how to honor her and lay her to rest.

Jesperson was arrested in 1995, and eventually confessed to killing eight women between 1990 and 1995 in California, Washington state, Oregon, Florida, Nebraska and Wyoming.

He became known as the "Happy Face Killer" after sending letters about his crimes to the media that he signed with a smiley face.

He pleaded guilty to McWhorter's murder in Riverside County on Jan. 8, 2010, and was sentenced to 25 years to life in prison. 

He is serving multiple life sentences in Oregon.

With McWhorter's identification, Riverside County's cold case team has now closed the final unidentified-victim case tied to the murders for which Jesperson was convicted.