Final answer:
Elie's father does not allow him to sleep because he is burdened by traumatic memories and a profound fear of sleep, which is a recurring theme in literature where characters are shown struggling with past traumas and their impacts on sleep.
Step-by-step explanation:
Elie's father does not allow him to sleep because he is haunted by traumatic memories and fears. Trauma and the fear of nightmares can be so intense that the thought of sleep brings more distress than relief. This can be seen in various works of literature where characters struggle with their past experiences, such as the man in LibreTexts who is so attached to the house he built that he cannot bear to leave it, or the adult in the narrative who is unable to fall asleep due to a smell of cats.
Distressing thoughts and the avoidance of sleep serve as mechanisms for dealing with trauma, as exemplified by the great-uncle in the cited text who had to sleep against a wall due to the nightmares of witnessing his family's murder. These excerpts highlight the complex relationship between trauma, memory, and the inability to find rest in sleep.