The preliminary cause of death is stabbing, Petitt said. Tammy Weeks, Lovell's mother, read a statement at the press conference, which you can hear in the video above. She was overcome by emotion and had to walk away before she finished. She did make it clear that Lovell had survived medical complications at a young age, and it is hard to grasp that her daughter overcame such odds only to perish at the hands of a murderer.
Nicole went missing sometime in the wee hours of January 27
Why? Why would a 13-year-old girl be killed? And why -- if authorities' suspicions are correct -- would two college students, at least, have a role in killing her?
Investigators continued their efforts Tuesday to answer these and many other questions related to the death of Nicole Madison Lovell, a middle-school student in Blacksburg. Nicole went missing sometime in the wee hours of January 27, spurring an extensive search that ended the discovery of her body in a wooded area off Route 89 in Surry County, North Carolina.
Hours earlier, police arrested David E. Eisenhauer on one felony abduction count. Authorities later tacked on a murder charge, and on Sunday announced a Keepers charge for allegedly helping dispose of the girl's body.
Lawyers for both Eisenhauer, 18, and Keepers, 19, have both declined to talk to CNN thus far. The closest to a statement may have come in a court document in which Eisenhauer is quoted as saying, "The truth will set me free."
Blacksburg police Chief Anthony Wilson spent part of Tuesday morning talking to Nicole's mother, Tammy Weeks, leaving the family's apartment around 10:45 a.m.
Kendrick Todd Brewster, a member of Blacksburg's police department, told CNN on Tuesday that the family had no plans to talk to the media anytime soon. He spoke from inside the family's home, one of 120 or so units in the Lantern Ridge Apartments complex located amid a maze of mostly student housing roughly a half mile from Blacksburg's Main Street, which takes you downtown and to Virginia Tech's campus.
On the patio outside, there was evidence of more carefree times: a bicycle, a yellow Tonka truck, a few plastic chairs. A small bouquet of pink and white flowers rested on a table, in the low 40-something temperatures, a reminder of the family's inconceivable loss.
As Nicole's friend Sarah Bradbury told CNN affiliate WBDJ this past weekend, "I didn't think that would happen to her because she was always the cutest little thing."
Girl had survived liver transplant, lymphoma
Earlier, Weeks told The Washington Post her daughter survived a liver transplant, MRSA and lymphoma when she was 5. She was a seventh-grader -- "a typical student," according to her mother -- at Blacksburg Middle School, though one who still had her difficulties.
"She didn't like going to school because she was bullied," Weeks said. "She was telling me that girls were saying she was fat and talking about her scars from her transplant."
Authorities haven't indicated that anyone who attended school with Nicole had anything to do with her disappearance. On the contrary, Eisenhauer and Keepers both attended Virginia Tech in Blacksburg.
But Eisenhauer -- a celebrated cross-country runner in Columbia, Maryland, prior to coming to Virginia Tech -- at least knew her, according to police.
"We have determined that Eisenhauer and Nicole were acquainted prior to her disappearance," Blacksburg police Lt. Mike Albert told reporters last weekend. "Eisenhauer used this relationship to his advantage to abduct and then kill her."
Police connected the Virginia Tech student late Friday night. He was already facing charges the next morning, before Nicole's body was found around 4 p.m. Saturday about 80 miles south, just over the Virginia border.
Eisenhauer did not lead authorities to the body, according to Blacksburg's police chief, nor did he confess to murder. Still, authorities managed to piece things together after sorting through social media, exploring 300-plus tips and searching for other information pertinent to the case.
That investigation continues, part of an effort to bring clarity and closure to an unfathomable death.
"These are the kind of crimes," Wilson said last weekend, "that rip communities apart."
CNN's Eliott McLaughlin reported from Blacksburg, and CNN's Greg Botelho reported and wrote from Atlanta. CNN's Michael Pearson, Ralph Ellis, Shawn Nottingham, Nick Valencia, Joshua Berlinger and Carma Hassan contributed to this report.