The remains of a woman found in Arizona last month were confirmed Tuesday as those of 31-year-old Suellen Roberts, authorities said.
The Yavapai County sheriff's office said Roberts' family in Las Vegas has been notified.
Roberts' body was found near Seligman, Ariz.
The location is about 40 miles from the amusement park that she and 12-year-old daughter Lexis Roberts planned to visit with Suellen Roberts' boyfriend, Thomas Steven "Spider" Sanders, who was arrested in Mississippi last month.
Lexis' body was found Oct. 8 by hunters in the woods of central Louisiana.
Relatives of Roberts told the Review-Journal that Sanders had cooperated with the FBI after his arrest on Nov. 14 and told authorities where to find Roberts' body.
Sanders is facing a federal kidnapping charge related to Lexis' disappearance. If convicted, Sanders could face life in prison or the death penalty, authorities said.
Authorities in Louisiana said Sanders will be charged with murder in state court when the federal government finishes processing him.
Sanders, who was declared legally dead 16 years ago, was targeted in a nationwide manhunt after the mother and daughter were reported missing after Labor Day weekend.
The FBI coordinated the investigation, which involved multiple law enforcement agencies and four states.
Contact reporter Mike Blasky at firstname.lastname@example.org or 702-383-0283.