Foster was last seen in the company of her childhood friend Jeremy Bechtel, who is also missing. They visited a mutual friend that day, then left the friend's house in Foster's black two-door 1998 Pontiac Grand Am with the Tennessee license plate number 473EJR. Witnesses saw Bechtel and Foster in the car outside of Sparta, Tennesee at approximately 10:00 p.m. on April 3, 2000. They have never been heard from again and Foster's car is also missing.

At first investigators believed Bechtel and Foster had left of their own accord, but the passage of time has made this theory less likely. Since their disappearances there has been no activity on their Social Security numbers, and Foster never renewed her driver's license. The circumstances surrounding their cases are unclear. Both remain missing and their cases are unsolved.