Timeline of Alleged Abduction and Slaying of 13-Year-Old Virginia Girl

— -- A new charge has been brought against one of the suspects who police say was involved in death of Nicole Lovell, a 13-year-old girl in Blacksburg, Virginia.

David Eisenhauer, 18, and Natalie Keepers, 19, are in custody after being arrested in connection to the case, but new details released by investigators Tuesday give more insight into how the alleged crime may have unfolded.

Here is a timeline of how the case has been handled so far:

Wednesday, Jan. 27

Nicole was last seen at about midnight Wednesday morning, according to the Blacksburg police department officials, who immediately issued alerts that morning.

At the time, they noted that she had a tracheotomy scar on her throat and "requires prescription medication daily from a previous liver transplant and is currently without it," police wrote on her missing person’s poster.

Nicole's mom, Tammy Weeks, told The Washington Post that her daughter's nightstand had been pushed up against her bedroom door and her window was ajar when they discovered she was missing.

Police have since announced that they believe Nicole was killed "on or about" the day she went missing.

Friday, Jan. 29

The investigation leads police to Eisenhauer, an 18-year-old engineering student at Virginia Tech, which is in Blacksburg.

Saturday, Jan. 30

Early that morning, Eisenhauer was arrested in his Virginia Tech dorm room. He was charged with a felony count of abduction.

4:00 p.m.

Later that day, Virginia State Police locate the remains of Nicole about 80 miles south of her home.

The body was found not far from an exit on Route 89 in Surry County, North Carolina.

Eisenhauer was charged with a felony count of murder, as well as the previous abduction charge. When they first charged Eisenhauer, the alleged offense date was listed as Jan. 30, but police have since noted that they will be changing that to Jan. 27, the day that Nicole went missing.

Sunday, Jan. 31

Keepers was arrested that morning and charged with a felony count of improper disposal of a dead body and a misdemeanor count of accessory after the fact in the commission of a felony.

That same morning, Nicole’s remains were transported to the medical examiner's office in Roanoke, Virginia.

"Based on the evidence collected to date, investigators have determined that Eisenhauer and Nicole were acquainted prior to her disappearance,” Blacksburg police said in a statement released Sunday. “Eisenhauer used this relationship to his advantage to abduct the 13-year-old and then kill her.”

Monday, Feb. 1

Eisenhauer and Keepers had their separate arraignments at Montgomery County Juvenile and Domestic Relations Court, appearing briefly while wearing orange jumpsuits and shackles. Their preliminary hearings were set for late-March and neither has had to enter a plea. Neither of their attorneys has made any public statements about the case.

Tuesday, Feb. 2

Nicole's mother tearfully read a statement at a police news conference, telling how her daughter "touched many people throughout her short life."

Montgomery County Commonwealth’s Attorney Mary Pettitt revealed that a "preliminary determination of the cause of death is stabbing."

The charges against Keepers were increased that morning as well, as Pettitt announced that Keepers will be facing an additional charge of being an accessory before the fact to the first-degree murder of Nicole. That additional charge came on top of her previous charges of concealing a dead body and being an accessory after the fact.

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