Who is Linda Furstenburg from Subterranean and what is their importance?

Linda Furstenburg is a biologist. She is admittedly claustrophobic, but she carries pills with her so that she can handle the confinement of the caverns. Linda is forced to help Khalid, and although she does whatever she can to try and save those that Khalid is trying to hurt, she often feels that she has failed. Linda takes on the responsibility of looking after Jason after Dr. Blakely's death.