CHRISTIANSBURG, VA. -- Court documents show a Virginia Tech student accused of killing a 13-year-old girl said he might have had sex with the girl and was worried she was pregnant.

Nineteen-year-old David Eisenhauer is charged with first-degree murder in Nicole Lovell’s death. The two had communicated over the messaging app Kik. “48 Hours” investigated the case in the episode, “Killer App.”

Twenty-year-old Natalie Keepers is charged with accessory before the fact and concealing a body. Eisenhauer and Keepers are Maryland natives who were freshmen at Virginia Tech when Nicole was slain in January 2016.

The Roanoke Times reports that according to court documents filed last week, Keepers told investigators that Eisenhauer met Nicole at a party and was worried he might have had sex with her, but couldn’t remember because he blacked out. She also told police Eisenhauer feared the girl was pregnant.

Keepers is scheduled for trial in March.