User blog comment:FirstDrellSpectre/Fanfiction - Lori's 18/@comment-33195596-20160913000219

At the time Lori is eighteen, she might have already graduated from high school. My best guess is that she was born between September 1998 and December 1998. Also Linc or Swim reveals that she is in twelfth grade, and obviously takes place in the summer according to Lincoln. Lori most likely graduated from high school when Linc or Swim happened.