Claudia's Mother is a woman imagined by Glen, and was part of his murderous fantasy nightmare in which he massacres her family.
She was killed by Glen when she was taking a shower. He tried sneaking up on her with his knife. When he pulled away the shower curtain, she screamed and tried to cover her bare breasts. In her panic, Glen stabs her, causing her to slip and bash her head on the floor.
- Her death is an allusion to the classic shower scene of Psycho.